Intrinsic supercurrent non-reciprocity coupled to the crystal structure of a van der Waals Josephson barrier. (arXiv:2303.13049v1 [cond-mat.supr-con])

2023-03-24T04:30:32+00:00March 24th, 2023|Categories: Publications|Tags: , |

Non-reciprocal electronic transport in a spatially homogeneous system arises from the simultaneous breaking of inversion and time-reversal symmetries. Superconducting and Josephson diodes, a key ingredient for future non-dissipative quantum devices, have recently been realized. Only a few examples of a vertical superconducting diode effect have been reported and its mechanism, especially whether intrinsic or extrinsic, remains elusive. Here we demonstrate a substantial supercurrent non-reciprocity in a van der Waals vertical Josephson junction formed with a Td-WTe2 barrier and NbSe2 electrodes that clearly reflects the intrinsic crystal structure of Td-WTe2. The Josephson diode efficiency increases with the Td-WTe2 thickness up to critical thickness, and all junctions, irrespective of the barrier thickness, reveal magneto-chiral characteristics with respect to a mirror plane of Td-WTe2. Our results, together with the twist-angle-tuned magneto-chirality of a Td-WTe2 double-barrier junction, show that two-dimensional materials promise vertical Josephson diodes with high efficiency and tunability.

Published : "arXiv Mesoscale and Nanoscale Physics".

Probing interlayer van der Waals strengths of two-dimensional surfaces and defects, through STM tip-induced elastic deformations. (arXiv:2303.03712v1 [cond-mat.mtrl-sci])

2023-03-08T02:29:25+00:00March 8th, 2023|Categories: Publications|Tags: , |

A methodology to test the interlayer bonding strength of two-dimensional (2D) surfaces and associated one (1D)- and two (2D)- dimensional surface defects using scanning tunneling microscope tip-induced deformation, is demonstrated. Surface elastic deformation characteristics of soft 2D monatomic sheets of graphene and graphite in contrast to NbSe2 indicates related association with the underlying local bonding configurations. Surface deformation of 2D graphitic moire patterns reveal the inter-layer van der Waals strength varying across its domains. These results help in the understanding of the comparable interlayer bonding strength of 1D grain boundary as well as the grains. Anomalous phenomena related to probing 2D materials at small gap distances as a function of strain is discussed.

Published in: "arXiv Material Science".

Layer sliding and twisting induced electronic transitions in correlated magnetic 1T-NbSe2 bilayers. (arXiv:2302.04091v1 [cond-mat.mtrl-sci])

2023-02-09T02:29:20+00:00February 9th, 2023|Categories: Publications|Tags: , , , |

Correlated two-dimensional (2D) layers, like 1T-phases of TaS2, TaSe2 and NbSe2, exhibit rich tunability through varying interlayer couplings, which promotes the understanding of electron-correlation in the 2D limit. However, the coupling mechanism is, so far, poorly understood and was tentatively ascribed to interactions among the d_(z^2 ) orbitals of Ta or Nb atoms. Here, we theoretically show that the interlayer hybridization and localization strength of interfacial Se pz orbitals, rather than Nb d_(z^2 ) orbitals, govern the variation of electron-correlated properties upon interlayer sliding or twisting in correlated magnetic 1T-NbSe2 bilayers. Each of the both layers is in a star-of-David (SOD) charge-density-wave phase. Geometric and electronic structures, and magnetic properties of 28 different stacking configurations were examined and analyzed using density-functional-theory calculations. We found that the SOD contains a localized region (Reg-L), in which interlayer Se pz hybridization plays a paramount role in varying the energy levels of the two Hubbard bands. These variations lead to three electronic transitions among four insulating states, which demonstrated the effectiveness of interlayer interactions to modulate correlated magnetic properties in a prototypical correlated magnetic insulator.

Published in: "arXiv Material Science".

Correlated carrier dynamics in a superconducting van der Waals heterostructure. (arXiv:2301.03473v1 [cond-mat.supr-con])

2023-01-10T02:29:41+00:00January 10th, 2023|Categories: Publications|Tags: , , |

The study of Berezinskii-Kosterlitz-Thouless transitions in clean, layered two-dimensional superconductors promises to provide insight into a host of novel phenomena like re-entrant vortex-dynamics, underlying unconventional metallic phases, and topological superconductivity. In this letter, we report the study of charge carrier dynamics in a novel 2-dimensional superconducting van der Waals heterostructure comprising monolayer MoS2 and few-layer NbSe2 (15 nm). Using low-frequency conductance fluctuation spectroscopy, we show that the superconducting transition in the system is percolative. We present a phenomenological picture of different phases across the transition correlating with the evaluated noise. The analysis of the higher-order statistics of fluctuation reveals non-Gaussian components around the transition indicative of long-range correlation in the system.

Published in: "arXiv Material Science".

Chiral Topological superconductivity in the OAI/SC/FMI heterostructure avoiding the subband problem. (arXiv:2301.02510v1 [cond-mat.mtrl-sci])

2023-01-09T02:29:29+00:00January 9th, 2023|Categories: Publications|Tags: , |

Implementing topological superconductivity (TSC) and Majorana states (MSs) is one of the most significant and challenging tasks in both fundamental physics and topological quantum computations. In this work, taking the obstructed atomic insulator (OAI) Nb3Br8, s-wave superconductor (SC) NbSe2 and ferromagnetic insulator (FMI) as example, we propose a new setup to realize the 2D chiral TSC and MSs in the OAI/SC/FMI heterostructure, which could avoid the subband problem effectively and has the advantage of huge Rashba spin-orbit coupling. As a result, the TSC phase can be stabilized in a wide region of chemical potential and Zeeman field, and four distinct TSC phases with superconducting Chern number N= -1, -2, -3, 3 can be achieved. Moreover, a 2D BdG Hamiltonian based on the triangular lattice of obstructed Wannier charge centers, combined with the s-wave superconductivity paring and Zeeman field, is constructed to understand the whole topological phase diagram analytically. These results expand the application of OAIs and pave a new way to realize the TSC and MSs with unique advantages.

Published in: "arXiv Material Science".

Charge order with unusual star-of-David lattice in monolayer NbTe2. (arXiv:2212.12853v1 [cond-mat.mtrl-sci])

2022-12-27T02:29:21+00:00December 27th, 2022|Categories: Publications|Tags: , , |

Interplay between fermiology and electron correlation is crucial for realizing exotic quantum phases. Transition-metal dichalcogenide (TMD) 1T-TaS2 has sparked a tremendous attention owing to its unique Mott-insulating phase coexisting with the charge-density wave (CDW). However, how the fermiology and electron correlation are associated with such properties has yet to be claried. Here we demonstrate that monolayer 1T-NbTe2 is a new class of two-dimensional TMD which has the star-of-David lattice similarly to bulk TaS2 and isostructural monolayer NbSe2, but exhibits a metallic ground state with an unusual lattice periodicity root19xroot19 characterized by the sparsely occupied star-of-David lattice. By using angle-resolved photoemission and scanning-tunneling spectroscopies in combination with first-principles band-structure calculations, we found that the hidden Fermi-surface nesting and associated CDW formation are a primary cause to realize this unique correlated metallic state with no signature of Mott gap. The present result points to a vital role of underlying fermiology to characterize the Mott phase of TMDs.

Published in: "arXiv Material Science".

Unconventional Fulde-Ferrell-Larkin-Ovchinnikov state in a two-dimensional Ising superconductor. (arXiv:2211.07745v1 [cond-mat.supr-con])

2022-11-16T02:29:33+00:00November 16th, 2022|Categories: Publications|Tags: |

The conventional Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) state relies on the Zeeman effect of an external magnetic field to break time-reversal symmetry, forming a state of finite-momentum Cooper pairing. In superconductors with broken inversion symmetries, the Rashba or Ising-type spin-orbit coupling (SOC) can interact with either the Zeeman or the orbital effect of magnetic fields, extending the range of possible FFLO states, though evidence for these more exotic forms of FFLO pairing has been lacking. Here we report the discovery of an unconventional FFLO state induced by coupling the Ising SOC and the orbital effect in multilayer 2H-NbSe2. Transport measurements show that the translational and rotational symmetries are broken in the orbital FFLO state, providing the hallmark signatures of finite momentum cooper pairings. We establish the entire orbital FFLO phase diagram, consisting of normal metal, uniform Ising superconducting phase, and a six-fold orbital FFLO state. This study highlights an alternative route to finite-momentum superconductivity and provides a universal mechanism to prepare orbital FFLO states in similar materials with broken inversion symmetries.

Published in: "arXiv Material Science".

Revealing the Charge Density Wave caused by Peierls instability in two-dimensional NbSe2. (arXiv:2211.01203v1 [cond-mat.mtrl-sci])

2022-11-03T02:29:25+00:00November 3rd, 2022|Categories: Publications|Tags: |

The formation of the charge density wave (CDW) in two-dimensional (2D) materials caused by Peierls instability remains controversial. The role played by Fermi surface nesting in giving the CDW state in the 2H-NbSe2 material has been debated and is to be investigated here. Four NbSe2 structures, Normal, Stripe, Filled, and Hollow ones, have been identified based on the characteristics in scanning tunneling microscope images and first-principles simulations. The calculations reveal that the Filled phase follows Peierls’s description in exhibiting fully opened gaps at the CDW Brillouin zone boundary, resulting in a drop at the Fermi level in the density of states (DOS) and the scanning tunneling spectroscopy spectra. The electronic susceptibility and phonon instability in the Normal phase further support that the Fermi surface nesting is triggered by two nesting vectors, whereas solely one vector leads to the Stripe phase. This comprehensive study demonstrates that the Filled phase of NbSe2 can be categorized into the Peierls-instability-induced CDW in 2D systems.

Published in: "arXiv Material Science".

Spontaneous spin-valley polarization in NbSe2 at a van der Waals interface. (arXiv:2208.13150v2 [cond-mat.mes-hall] UPDATED)

2022-09-01T04:30:40+00:00September 1st, 2022|Categories: Publications|Tags: , |

A proximity effect at a van der Waals (vdW) interface enables creation of an emergent quantum electronic ground state. Here we demonstrate that an originally-superconducting two-dimensional (2D) NbSe2 forms a ferromagnetic ground state with spontaneous spin polarization at a vdW interface with a 2D ferromagnet V5Se8. We investigated the anomalous Hall effect (AHE) of the NbSe2/V5Se8 magnetic vdW heterostructures, and found that the sign of the AHE was reversed as the number of the V5Se8 layer was thinned down to the monolayer limit. Interestingly, the AHE signal of those samples was enhanced with the in-plane magnetic fields, suggesting an additional contribution to the AHE signal other than magnetization. This unusual behavior is well reproduced by band structure calculations, where the emergence of the Berry curvature along the spin-degenerate nodal lines in 2D NbSe2 by the in-plane magnetization plays a key role, unveiling a unique interplay between magnetism and Zeeman-type spin-orbit interaction in a non-centrosymmetric 2D quantum material.

Published : "arXiv Mesoscale and Nanoscale Physics".

Spontaneous spin-valley polarization in NbSe2 at a van der Waals interface. (arXiv:2208.13150v2 [cond-mat.mes-hall] UPDATED)

2022-09-01T02:29:26+00:00September 1st, 2022|Categories: Publications|Tags: , |

A proximity effect at a van der Waals (vdW) interface enables creation of an emergent quantum electronic ground state. Here we demonstrate that an originally-superconducting two-dimensional (2D) NbSe2 forms a ferromagnetic ground state with spontaneous spin polarization at a vdW interface with a 2D ferromagnet V5Se8. We investigated the anomalous Hall effect (AHE) of the NbSe2/V5Se8 magnetic vdW heterostructures, and found that the sign of the AHE was reversed as the number of the V5Se8 layer was thinned down to the monolayer limit. Interestingly, the AHE signal of those samples was enhanced with the in-plane magnetic fields, suggesting an additional contribution to the AHE signal other than magnetization. This unusual behavior is well reproduced by band structure calculations, where the emergence of the Berry curvature along the spin-degenerate nodal lines in 2D NbSe2 by the in-plane magnetization plays a key role, unveiling a unique interplay between magnetism and Zeeman-type spin-orbit interaction in a non-centrosymmetric 2D quantum material.

Published in: "arXiv Material Science".

Local density of state fluctuations in 2d multifractal superconductor. (arXiv:2207.14596v1 [cond-mat.supr-con])

2022-08-01T04:30:19+00:00August 1st, 2022|Categories: Publications|Tags: , |

The interplay of superconductivity and disorder is known to generate a wealth of new phenomena which have driven the history of superconductivity since its infancy. One of the major breakthroughs in the field is the celebrated quantum phase transition from superconductor to insulating state. Interestingly, the opposite effect has been reported several times : an increase of the superconducting critical temperature by disorder. One of the proposed mechanisms involves the peculiar structure of diffusive electronic wavefunctions whose multifractality can increase the superconducting pairing. Recent experiments in monolayer NbSe2 on graphene have reported Tc enhancement due to multifractal superconductivity but the theoretical models at our disposal fail to account for this effect at the relevant level of disorder. In this work, we use an epitaxial monolayer of lead showing a simple band structure and homogenous structural disorder as a model system of a 2d multifractal superconductor in the weak-antilocalization regime. Then, we perform an extensive study of the emergent fluctuations of local density of states in this material and compare them with both analytical results and numerical solution of the attractive Hubbard model. We show that mesoscopic LDOS fluctuations allow to probe locally elastic and inelastic scattering in 2d weakly disordered materials in particular in the most interesting multifractal regime.

Published : "arXiv Mesoscale and Nanoscale Physics".

Interior and edge magnetization in thin exfoliated CrGeTe3 films. (arXiv:2207.08845v1 [cond-mat.mes-hall])

2022-07-20T04:30:35+00:00July 20th, 2022|Categories: Publications|Tags: |

CrGeTe3 (CGT) is a semiconducting vdW ferromagnet shown to possess magnetism down to a two-layer thick sample. Although CGT is one of the leading candidates for spintronics devices, a comprehensive analysis of CGT thickness dependent magnetization is currently lacking. In this work, we employ scanning SQUID-on-tip (SOT) microscopy to resolve the magnetic properties of exfoliated CGT flakes at 4.2 K. Combining transport measurements of CGT/NbSe2 samples with SOT images, we present the magnetic texture and hysteretic magnetism of CGT, thereby matching the global behavior of CGT to the domain structure extracted from local SOT magnetic imaging. Using this method, we provide a thickness dependent magnetization state diagram of bare CGT films. No zero-field magnetic memory was found for films thicker than 10 nm and hard ferromagnetism was found below that critical thickness. Using scanning SOT microscopy, we identify a unique edge magnetism, contrasting the results attained in the CGT interior.

Published : "arXiv Mesoscale and Nanoscale Physics".

Controllable dimensionality conversion between 1D and 2D CrCl3 magnetic nanostructures. (arXiv:2207.02658v1 [cond-mat.mtrl-sci])

2022-07-07T02:29:35+00:00July 7th, 2022|Categories: Publications|Tags: |

The fabrication of one-dimensional (1D) magnetic systems on solid surfaces, although of high fundamental interest, has yet to be achieved for a crossover between two-dimensional (2D) magnetic layers and their associated 1D spin chain systems. In this study, we report the fabrication of 1D single unit-cell-width CrCl3 atomic wires and their stacked few-wire arrays on the surface of a van der Waals (vdW) superconductor NbSe2. Scanning tunneling microscopy/spectroscopy and first-principles calculations jointly determined the wire to be an antiferromagnetic large-bandgap semiconductor with an unexplored structure different from the well-known 2D CrCl3 phase. Competitions among the total energies, edge (end)-substrate interactions, and nanostructure-substrate interfacial interactions of these two phases result in the appearance of the 1D phase. This phase was transformable to the 2D phase either prior to or after the growth for in-situ or ex-situ manipulations, in which the interfacial vdW interactions played a nontrivial role that could regulate the dimensionality conversion and structural transformation between the 1D-2D CrCl3 phases.

Published in: "arXiv Material Science".

Leggett Modes in Dirac Semimetals. (arXiv:2205.15995v1 [cond-mat.supr-con])

2022-06-01T04:30:32+00:00June 1st, 2022|Categories: Publications|Tags: |

In recent years experimentalists have been able to clearly show that several materials, such as MgB2, iron-based superconductors3, monolayer NbSe2, are multiband superconductors. Superconducting pairing in multiple bands can give rise to novel and very interesting phenomena. Leggett modes are exemplary of the unusual effects that can be present in multiband superconductors. A Leggett mode describes the collective periodic oscillation of the relative phase between the phases of the superconducting condensates formed by electrons in different bands. It can be thought of as the mode arising from an inter-band Josephson effect. The experimental observation of Leggett modes is challenging for several reasons: (i) Multiband superconductors are rare; (ii) they describe charge fluctuations between bands and therefore are hard to probe directly; (iii) their mass gap is often larger than the superconducting gaps and therefore are strongly overdamped via relaxation processes into the quasiparticle continuum. In this work we show that Leggett modes, and their frequency, can be detected unambigously in a.c. driven superconducting quantum interference devices (SQUIDs). We then use the results to analyze the measurements of a SQUID based on Cd3As2, an exemplar Dirac semimetal, in which superconductivity is induced by proximity to superconducting Al. The experimental results show the theoretically predicted unique signatures of Leggett modes and therefore allow us to conclude that a Leggett mode is present in the two-band superconducting state of Dirac semimetal (DSM) Cd3As2.

Published : "arXiv Mesoscale and Nanoscale Physics".

Charge to Spin Conversion in van der Waals Metal NbSe2. (arXiv:2205.08327v1 [cond-mat.mes-hall])

2022-05-18T04:30:32+00:00May 18th, 2022|Categories: Publications|Tags: , |

Quantum materials with a large charge current-induced spin polarization are promising for next-generation all-electrical spintronic science and technology. Van der Waals metals with high spin-orbit coupling and novel spin textures have attracted significant attention for an efficient charge to spin conversion process. Here, we demonstrate the electrical generation of spin polarization in NbSe2 up to room temperature. To probe the current-induced spin polarization in NbSe2, we used a graphene-based non-local spin-valve device, where the spin-polarization in NbSe2 is efficiently injected and detected using non-local spin-switch and Hanle spin precession measurements. A significantly higher charge-spin conversion in NbSe2 is observed at a lower temperature, below the superconducting transition temperature Tc ~ 7 K of NbSe2. However, the charge-spin conversion signal could only be observed with a higher bias current above the superconducting critical current, limiting the observation of the signal only to the non-superconducting state of NbSe2. Systematic measurements provide the possible origins of the spin polarization to be predominantly due to the spin Hall effect or Rashba-Edelstein effect in NbSe2, considering different symmetry allowed charge-spin conversion processes.

Published : "arXiv Mesoscale and Nanoscale Physics".

Crossover of Ising- to Rashba-Type Superconductivity in Epitaxial Bi2Se3/Monolayer NbSe2 Heterostructures. (arXiv:2112.14623v3 [cond-mat.supr-con] UPDATED)

2022-04-20T04:30:33+00:00April 20th, 2022|Categories: Publications|Tags: , , |

A topological insulator (TI) interfaced with an s-wave superconductor has been predicted to host an unusual form of superconductivity known as topological superconductivity (TSC). Molecular beam epitaxy (MBE) has been the primary approach in the scalable synthesis of the TI/superconductor heterostructures. Although the growth of epitaxial TI films on s-wave superconductors has been achieved, it remains an outstanding challenge for synthesizing atomically thin TI/superconductor heterostructures, which are critical for engineering the TSC phase. Here, we used MBE to grow Bi2Se3 films with the controlled thickness on monolayer NbSe2 and performed in-situ angle-resolved photoemission spectroscopy and ex-situ magneto-transport measurements on these Bi2Se3/monolayer NbSe2 heterostructures. We found that the emergence of Rashba-type bulk quantum well bands and spin-nondegenerate surface states coincides with a marked suppression of the in-plane upper critical magnetic field of the superconductivity in Bi2Se3/monolayer NbSe2 heterostructures. This is the signature of a crossover from Ising- to Rashba-type superconducting pairings, induced by altering Bi2Se3 film thickness. Our work opens a new route for exploring a robust TSC phase in TI/Ising superconductor heterostructures.

Published : "arXiv Mesoscale and Nanoscale Physics".

Nonlinear optical Hall effect of few-layered NbSe2. (arXiv:2203.12767v1 [cond-mat.mes-hall])

2022-03-25T04:30:30+00:00March 25th, 2022|Categories: Publications|Tags: |

NbSe$_2$ is one of metallic two-dimensional (2D) transition-metal dichalcogenide (TMDC) materials. Because of broken crystal inversion symmetry, large spin splitting is induced by Ising-type spin-orbit coupling in odd-number-layered NbSe$_2$, but absent for even-number-layered NbSe$_2$ with the inversion symmetry. In this paper, we numerically calculate nonlinear optical charge and spin Hall conductivities of few-layered NbSe$_2$ based on an effective tight-binding model which includes $d_{z^2}$, $d_{x^2-y^2}$ and $d_{xy}$ orbitals of Nb atom. We show that the nonlinear optical Hall conductivity for second harmonic generation (SHG) process has nonvanishing value in odd-number-layered NbSe$_2$. Also, we provide nonlinear optical selection rule in few-layered NbSe$_2$ and their polarization dependences. In further, for even-number-layered case, the nonlinear optical Hall currents can be generated by applying electric fields which break inversion symmetry. We also discuss that the nonlinear optical Hall effect is expected to occur in TMDC materials in general. Thus, our results will serve to design potential opt-spintronics devices based on 2D materials to generate the spin Hall current by SHG.

Published : "arXiv Mesoscale and Nanoscale Physics".

Nonlinear optical Hall effect of few-layered NbSe2. (arXiv:2203.12767v1 [cond-mat.mes-hall])

2022-03-25T02:29:33+00:00March 25th, 2022|Categories: Publications|Tags: |

NbSe$_2$ is one of metallic two-dimensional (2D) transition-metal dichalcogenide (TMDC) materials. Because of broken crystal inversion symmetry, large spin splitting is induced by Ising-type spin-orbit coupling in odd-number-layered NbSe$_2$, but absent for even-number-layered NbSe$_2$ with the inversion symmetry. In this paper, we numerically calculate nonlinear optical charge and spin Hall conductivities of few-layered NbSe$_2$ based on an effective tight-binding model which includes $d_{z^2}$, $d_{x^2-y^2}$ and $d_{xy}$ orbitals of Nb atom. We show that the nonlinear optical Hall conductivity for second harmonic generation (SHG) process has nonvanishing value in odd-number-layered NbSe$_2$. Also, we provide nonlinear optical selection rule in few-layered NbSe$_2$ and their polarization dependences. In further, for even-number-layered case, the nonlinear optical Hall currents can be generated by applying electric fields which break inversion symmetry. We also discuss that the nonlinear optical Hall effect is expected to occur in TMDC materials in general. Thus, our results will serve to design potential opt-spintronics devices based on 2D materials to generate the spin Hall current by SHG.

Published in: "arXiv Material Science".

Atomic-Scale Visualization of Chiral Charge Density Wave States and Their Reversible Transition. (arXiv:2203.09212v1 [cond-mat.mtrl-sci])

2022-03-18T02:30:07+00:00March 18th, 2022|Categories: Publications|Tags: |

Chirality is essential for various amazing phenomena in life and matter. However,chirality and its switching in electronic superlattices, such as charge density wave(CDW) arrays, remain elusive. In this study, we characterize the chirality transition with atom-resolution imaging in a single-layer NbSe2 CDW pattern by technique of scanning tunneling microscopy. The atomic lattice of the CDW array is found continuous and intact although its chirality is switched. Several intermediate states are tracked by time-resolved imaging, revealing the fast and dynamic chirality transition. Importantly, the switching is reversibly realized with an external electric-field. Our findings unveil the delicate transition process of chiral CDW array in a 2D crystal down to the atomic scale and may be applicable for future nanoscale devices.

Published in: "arXiv Material Science".

Structure Analysis using Time-of-Flight Momentum Microscopy with Hard X-rays: Status and Prospects. (arXiv:2202.11951v1 [cond-mat.mtrl-sci])

2022-02-25T02:29:18+00:00February 25th, 2022|Categories: Publications|Tags: |

X-ray photoelectron diffraction (XPD) has developed into a powerful technique for the structural analysis of solids. Extension of the technique into the hard-X-ray range (hXPD) gives access to true bulk information. Here we give a status report on hXPD experiments using a novel full-field imaging technique: Time-of-flight momentum microscopy (ToF-MM). A special variant of ToF-MM is capable of recording high kinetic energies (up to >7keV) and enlarged k-fields-of-view. We present applications that are specific for high kinetic energies. The strong site specificity of hXPD is exemplified for NbSe2, the cubic-to-tetragonal transition in SrTiO3 and the zinc-blende structure in epitaxial GaAs films. Bloch-wave calculations show a very good agreement with experiment and reveal fingerprint-like signatures of emitter sites in host lattices. We show a dopant-site analysis in two semiconductors (Mn in GaAs and Te in Si). Hard-X-ray ARPES plus core-level hXPD enable eliminating the strong diffraction signature imprinted in HARPES maps.

Published in: "arXiv Material Science".

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