Article
Physics, Multidisciplinary
Jiabing Xiang, Paolo Molignini, Miriam Buettner, Axel U. J. Lode
Summary: Pauli crystals are ordered geometric structures that emerge in trapped noninteracting fermionic systems due to their underlying Pauli repulsion. The mechanism that leads to the melting of Pauli crystals remains unclear. In this study, we investigate the melting dynamics of N = 6 fermions as a function of periodic driving and experimental imperfections in the trap using numerical simulations and Floquet theory. We find that the melting of Pauli crystals is not simply driven by an increase in system energy, but is instead influenced by the trap geometry and the population of the Floquet modes.
Article
Physics, Multidisciplinary
Marvin Holten, Luca Bayha, Keerthan Subramanian, Carl Heintze, Philipp M. Preiss, Selim Jochim
Summary: The research reports on the direct observation of the Pauli exclusion principle in a continuous system of up to six particles in the ground state of a two-dimensional harmonic oscillator. The study found Pauli crystals as a manifestation of higher order correlations without any interactions present, laying the foundation for future studies of correlations in strongly interacting systems of many fermions.
PHYSICAL REVIEW LETTERS
(2021)
Article
Multidisciplinary Sciences
Su Kong Chong, Lizhe Liu, Kenji Watanabe, Takashi Taniguchi, Taylor D. Sparks, Feng Liu, Vikram V. Deshpande
Summary: Transport evidence of two-dimensional (2D) topological states in a bulk insulating three-dimensional (3D) topological insulator (TI) is provided. The existence of a finite longitudinal conductance at the surface gap suggests the emergence of a quantum spin Hall (QSH) state. The transition from QSH to quantum Hall (QH) state in a transverse magnetic field further supports the existence of this unique 2D topological phase. Another method of achieving the 2D topological state is demonstrated through surface gap-closing and topological phase transition mediated by a transverse electric field.
NATURE COMMUNICATIONS
(2022)
Article
Physics, Multidisciplinary
Juan Roman-Roche, Fernando Luis, David Zueco
Summary: A system of magnetic molecules coupled to microwave cavities undergoes the equilibrium superradiant phase transition, which is experimentally observable. The coupling effect is illustrated by the vacuum-induced ferromagnetic order in a quantum Ising model and the modification of the magnetic phase diagram of Fe-8 dipolar crystals, showcasing the cooperation between intrinsic and photon-induced spin-spin interactions. Finally, a transmission experiment demonstrates the quantum electrodynamical control of magnetism in resolving the transition.
PHYSICAL REVIEW LETTERS
(2021)
Article
Multidisciplinary Sciences
Victor Helson, Timo Zwettler, Farokh Mivehvar, Elvia Colella, Kevin Roux, Hideki Konishi, Helmut Ritsch, Jean-Philippe Brantut
Summary: A density wave (DW) is a type of long-range order in quantum matter that is associated with self-organization into a crystalline structure. The interplay of DW order with superfluidity presents a significant theoretical challenge. In this study, a tunable quantum Fermi gas with both strong, contact interactions and photon-mediated, spatially structured long-range interactions in an optical cavity is realized. The DW order is stabilized in the system above a critical long-range interaction strength, which is identified through superradiant light-scattering properties. The experimental setup provides a fully tunable and microscopically controllable platform for studying the interplay of superfluidity and DW order.
Article
Multidisciplinary Sciences
An Wang, Feng Du, Yongjun Zhang, David Graf, Bin Shen, Ye Chen, Yang Liu, Michael Smidman, Chao Cao, Frank Steglich, Huiqiu Yuan
Summary: Ferromagnetic quantum criticality was observed in CeRh6Ge4 under moderate hydrostatic pressure, supported by quantum oscillation measurements. The study found that Ce 4f electrons remain localized and do not contribute to the Fermi surface, suggesting localized ferromagnetism as a key factor for the occurrence of a ferromagnetic quantum critical point in CeRh6Ge4.
Article
Chemistry, Multidisciplinary
Qile Li, Chi Xuan Trang, Weikang Wu, Jinwoong Hwang, David Cortie, Nikhil Medhekar, Sung-Kwan Mo, Shengyuan A. Yang, Mark T. Edmonds
Summary: Combining magnetism and nontrivial band topology can achieve the quantum anomalous Hall (QAH) effect at high temperatures for lossless transport applications. In this study, a heterostructure consisting of two single-septuple layers (1SL) of MnBi2Te4, an ultrathin few quintuple layer (QL) Bi2Te3, and another 1SL MnBi2Te4 was grown via molecular beam epitaxy. The electronic structure was probed using angle-resolved photoelectron spectroscopy, and strong hexagonally warped massive Dirac fermions and a bandgap of 75 +/- 15 meV were observed. The magnetic origin of the gap was confirmed, and these findings provide insights into magnetic proximity effects in topological insulators and a promising platform for realizing the QAH effect at elevated temperatures.
ADVANCED MATERIALS
(2022)
Article
Materials Science, Multidisciplinary
Ceren B. Dag, Kai Sun
Summary: This paper investigates the dynamical detection of quantum phases and phase transitions in quenched systems, revealing significant differences in scaling law exponent near the dynamical crossover between short and long times. It also shows that when integrability is strongly broken, the crossover boundary transforms into a region separating two other dynamical regions acting as dynamically ordered and disordered regimes.
Article
Materials Science, Multidisciplinary
Wei-Tao Lu, Qing-Feng Sun, Qiang Cheng
Summary: We studied the subgap transport in a ferromagnet/Ising superconductor/ferromagnet junction and found that the crossed Andreev reflection (CAR) and local Andreev reflection (LAR) strongly depend on the spin-polarized ferromagnet, magnetization direction, and Ising superconducting phase. For the same magnetization directions, equal-spin CAR can occur due to the spin-flip mechanism induced by the Ising spin-orbit coupling and equal-spin-triplet pairing. Both equal-spin CAR and equal-spin LAR show remarkable magnetoanisotropy with a period of pi and oscillatory behavior with chemical potential. The equal-spin CAR is more prominent with half-metal ferromagnet and double-band Ising superconductor while normal CAR is completely suppressed. In the case of different magnetization directions, oblique-spin CAR occurs with a magnetoanisotropic period of 2pi. The oblique-spin CAR process involves spins of the electron and hole that are neither parallel nor antiparallel. Furthermore, the property of oblique-spin CAR is very sensitive to the spin and valley degrees of freedom. Spin- and valley-polarized CAR can be achieved and controlled by the chemical potentials and magnetization directions.
Article
Chemistry, Multidisciplinary
Kajetan M. Fijalkowski, Nan Liu, Pankaj Mandal, Steffen Schreyeck, Karl Brunner, Charles Gould, Laurens W. Molenkamp
Summary: The recent emergence of topological states of matter has led to significant discoveries, including the quantum anomalous Hall effect, which has potential applications in quantum metrology and impacts fundamental research in topological and magnetic states, as well as axion electrodynamics. This study presents electronic transport studies on a (V,Bi,Sb)2Te3 ferromagnetic topological insulator nanostructure in the quantum anomalous Hall regime, allowing examination of individual ferromagnetic domains. The observed telegraph noise in the Hall signal is attributed to magnetization fluctuations of the domain, and analysis of temperature and external magnetic field effects provides evidence for quantum tunneling of magnetization in a macrospin state.
Article
Optics
Lane G. Gunderman
Summary: Transformations between fermionic modes and qubit operations are widely used in quantum algorithms for system simulation. Collections of Pauli operators can be obtained from nonlocal games and satisfiability problems. Building on concepts from entanglement-assisted quantum error-correcting codes and quantum convolutional codes, we prove the lower bound for the number of qubits required to represent equivalent Pauli operations and provide a method for determining minimal register Pauli operations.
Article
Optics
Daniel A. Paz, Mohammad F. Maghrebi
Summary: Driven-dissipative many-body systems are difficult to analyze due to their nonequilibrium dynamics, dissipation, and many-body interactions. In this paper, we developed an exact field-theoretical analysis and a diagrammatic representation of a driven-dissipative infinite-range Ising model, showing critical behavior, finite-size scaling, and the effective temperature near phase transitions. The study revealed distinct critical behaviors at phase transitions, with overdamped and underdamped dynamics depending on the dissipative critical points.
Article
Optics
Senrui Chen, Sisi Zhou, Alireza Seif, Liang Jiang
Summary: We demonstrate that entangled measurements provide an exponential advantage in sample complexity for Pauli channel estimation, which is a fundamental problem and a necessary subroutine for benchmarking near-term quantum devices. Through our research, we provide an estimation protocol using ancilla that significantly reduces the number of copies of the Pauli channel required for accurate estimation. We also explore the benefits of a limited number of ancillas and how to apply the estimation protocol to practical quantum benchmarking tasks.
Article
Physics, Condensed Matter
Tirthankar Chakraborty, Suja Elizabeth
Summary: The critical behavior at the ferromagnetic to paramagnetic phase transition of a Griffiths ferromagnet, Ho2NiMnO6, was studied using various methods. The results show that the system undergoes a second-order phase transition that does not belong to conventional universality classes, but follows scaling relationships. The presence of the Griffiths phase in the system explains the unusual critical behavior observed.
JOURNAL OF PHYSICS-CONDENSED MATTER
(2023)
Article
Optics
Matthew Ware, Guilhem Ribeill, Diego Riste, Colm A. Ryan, Blake Johnson, Marcus P. da Silva
Summary: This study demonstrates the implementation of Pauli-frame randomization in a superconducting circuit system to shape noise into more benign forms for quantum error correction and fault tolerance. By randomizing circuits, signatures of non-Markovian evolution are suppressed to statistically insignificant levels, while maintaining fidelity and even improving error rates. The randomization technique ensures rigorous statements about error properties and contributes to the scalability of quantum computing with imperfect qubits.
Article
Chemistry, Inorganic & Nuclear
Kasey P. Devlin, Junjie Zhang, James C. Fettinger, Eun Sang Choi, Ashlee K. Hauble, Valentin Taufour, Raphael P. Hermann, Susan M. Kauzlarich
Summary: The study presents the structure, magnetic properties, and Mossbauer spectra of the solid-solution Eu11-xSrxZn4Sn2As12. The compound Eu11Zn4Sn2As12 shows ferromagnetic coupling at 5K and colossal magnetoresistance at 15K. The investigation reveals a nontrivial correlation between structure and magnetization in the solid solution.
INORGANIC CHEMISTRY
(2021)
Article
Chemistry, Physical
Hanshang Jin, Jackson Badger, Peter Klavins, Jing-Tai Zhao, Valentin Taufour
Summary: Sub-oxides with anti-perovskite structure have unique chemical and physical properties, with a new compound synthesized and characterized with a complex crystal structure and metallic behavior. The stability of the compounds is influenced by chemical pressure and the ratio of atomic radii of rare earth and main group elements.
JOURNAL OF ALLOYS AND COMPOUNDS
(2021)
Article
Instruments & Instrumentation
X. D. Zhu, R. Ullah, V. Taufour
Summary: The oblique-incidence zero-area Sagnac interferometric microscope has the ability to independently measure the three Cartesian components of magnetization, making it useful for studying magnetic effects at low temperatures. Observing magnetic domains of LaCrGe3 crystal demonstrates the MO Kerr effect at different temperatures.
REVIEW OF SCIENTIFIC INSTRUMENTS
(2021)
Article
Physics, Multidisciplinary
Jackson R. Badger, Yundi Quan, Matthew C. Staab, Shuntaro Sumita, Antonio Rossi, Kasey P. Devlin, Kelly Neubauer, Daniel S. Shulman, James C. Fettinger, Peter Klavins, Susan M. Kauzlarich, Dai Aoki, Inna M. Vishik, Warren E. Pickett, Valentin Taufour
Summary: Unconventional superconductors have Cooper pairs with lower symmetries compared to conventional superconductors. This article demonstrates that the time-reversal symmetry breaking in the superconductor LaNiGa2 is enabled by its previously unknown topological electronic band structure. These unique topological features allow LaNiGa2 to break time-reversal symmetry in the absence of other typical ingredients, providing a pathway for identifying a new type of unconventional superconductors based on nonsymmorphic symmetries.
COMMUNICATIONS PHYSICS
(2022)
Article
Materials Science, Multidisciplinary
Journey K. Byland, Yunshu Shi, David S. Parker, Jingtai Zhao, Shaoqing Ding, Rogelio Mata, Haley E. Magliari, Andriy Palasyuk, Sergey L. Bud'ko, Paul C. Canfield, Peter Klavins, Valentin Taufour
Summary: This study proposes a method to search for new ferromagnetic compounds beyond known structure families using a database of experimental Curie and Neel temperatures. By focusing on cobalt-containing compounds, the use of this database helps discover previously overlooked ferromagnetic materials, which are confirmed through theoretical calculations and experimental synthesis.
PHYSICAL REVIEW MATERIALS
(2022)
Article
Physics, Condensed Matter
Zihao Shen, X. D. Zhu, Rahim R. Ullah, Peter Klavins, Valentin Taufour
Summary: In this study, we present the results of bulk magnetization measurements and spatially resolved measurements of magnetic domains in Co3Sn2S2.
JOURNAL OF PHYSICS-CONDENSED MATTER
(2023)
Article
Chemistry, Inorganic & Nuclear
Ashlee K. Hauble, Kamil Ciesielski, Valentin Taufour, Eric S. Toberer, Susan M. Kauzlarich
Summary: In this study, Ba2-xEuxZnSb2 was synthesized by substituting Eu for Ba to improve the stability of the material in air and to characterize its thermal and electronic properties. The samples exhibited low thermal conductivity (<0.8 W/m K), high Seebeck coefficient (350-550 mu V/K), and high charge carrier mobility (20-35 cm2/V) from 300 to 500 K, consistent with predictions of high thermoelectric efficiency. Evaluation of the thermoelectric quality factor suggests that a higher zT can be achieved by increasing the carrier concentration through doping.
INORGANIC CHEMISTRY
(2023)
Article
Physics, Applied
Joshua F. Belot, Valentin Taufour, Stefano Sanvito, Gus L. W. Hart
Summary: Researchers developed machine-learning models based on the chemical composition of materials to predict Curie temperatures. A random-forest model provided the most accurate predictions and did not require dimensionality reduction or complex descriptors. Cobalt-rich and iron-rich materials showed the highest Curie temperatures among binary and ternary compounds.
APPLIED PHYSICS LETTERS
(2023)
Article
Materials Science, Multidisciplinary
R. R. Ullah, P. Klavins, X. D. Zhu, V. Taufour
Summary: Two ferromagnetic phases, FM1 and FM2, were found to exist in LaCrGe3, and the domain structure undergoes a substantial change between these two phases. The measurements of the coercive field and magnetization curves reveal unconventional magnetic domain behavior in the FM1 phase, followed by a depinning region as the system transitions into the FM2 phase.
Article
Chemistry, Physical
Luke M. McClintock, Long Yuan, Ziyi Song, Michael T. Pettes, Dmitry Yarotski, Rijan Karkee, David A. Strubbe, Liang Z. Tan, Azza Ben-Akacha, Biwu Ma, Yunshu Shi, Valentin Taufour, Dong Yu
Summary: 1D organic metal halide hybrids (OMHHs) exhibit promising optical properties for photodetection and lighting applications, but the governing mechanisms and surface effects are not well understood. This study investigates the optical properties of 1D C4N2H14PbBr4 through polarization-dependent time-averaged and time-resolved photoluminescence spectroscopy. The results reveal an excitation-energy-dependent anisotropic emission, which is attributed to fast surface recombination confirmed by first-principles calculations and experimental measurements.
Article
Materials Science, Multidisciplinary
Adam L. Gross, Lorenz Falling, Matthew C. Staab, Metzli Montero, Rahim R. Ullah, David M. Nisson, Peter Klavins, Kristie J. Koski, Nicholas J. Curro, Valentin Taufour, Slavomir Nemsak, Inna M. Vishik
Summary: Using ambient pressure x-ray photoelectron spectroscopy, this study reveals the phenomenon of copper migration in CuxBi2Se3, which is accompanied by oxidation of the sample surface and significant changes in selenium content. The results suggest that surface chemical composition of intercalated TIs may change when exposed to ambient conditions.
JOURNAL OF PHYSICS-MATERIALS
(2022)
Article
Materials Science, Multidisciplinary
Hanshang Jin, Weizhao Cai, Jared Coles, Jackson R. Badger, Peter Klavins, Shanti Deemyad, Valentin Taufour
Summary: We compare the magnetic phase diagrams of CeTiGe3 under pressure and substitution by combining structural and magnetic measurements. The introduction of V doping in CeTi1-xVxGe3 suppresses the ferromagnetic ordering in CeTiGe3, suggesting a possible ferromagnetic quantum critical point near x = 0.45. Detailed crystalline electric field (CEF) analysis reveals a gradual change in the ground state from |+/- 5/2 > in CeTiGe3 to |+/- 1/2 > in CeVGe3, with a suppression of CEF splitting energies near the quantum critical region. The hydrostatic pressure study shows the appearance of magnetic phases above around 4.1GPa, avoiding the quantum critical point, while the substitution study separates the ferromagnetic and antiferromagnetic regions.
Article
Materials Science, Multidisciplinary
Yundi Quan, Valentin Taufour, Warren E. Pickett
Summary: The space group of the weakly correlated yet exotic time reversal symmetry breaking superconductor LaNiGa2 has been identified as nonsymmorphic Cmcm. This symmetry causes band sticking on a zone face pierced by four Fermi surfaces, leading to two nodal Fermi lines and a nodal Fermi loop. These nodal structures, influenced by the band sticking and distinctive Fermi surface placed Dirac points, establish LaNiGa2 as a topological superconductor.
Article
Materials Science, Multidisciplinary
Jackson R. Badger, Rumika Miyawaki, Zach E. Brubaker, Peter Klavins, Rena Zieve, Tatsuma D. Matsuda, Valentin Taufour
Summary: The Ce1-xNdxIn3 phase diagram was investigated in this study, revealing two distinct broad resistance peaks in the most disordered substitution region. The magnetic susceptibility and resistance data show competition between antiferromagnetic ordering in CeIn3 and NdIn3, with the antiferromagnetic transition of CeIn3 suppressed linearly when the concentration of Nd reaches around 0.6.
Article
Materials Science, Multidisciplinary
Yunshu Shi, David S. Parker, Eun Sang Choi, Kasey P. Devlin, Li Yin, Jingtai Zhao, Peter Klavins, Susan M. Kauzlarich, Valentin Taufour
Summary: Y2Co3 crystallizes in the La2Ni3-type orthorhombic structure with antiferromagnetic order, where moments align primarily along the b axis. Under pressure, the Néel temperature decreases.
Article
Materials Science, Multidisciplinary
Nizar Lefi, Salem Neily, Roland Bonnet
Summary: This paper investigates the elastic field in a bi-material crystal with an angular dislocation line with one branch placed in the crystal and the other along a strongly bound or welded interface. The analysis formulates the elastic field of a closed dislocation loop and solves it using the knowledge of the Green's tensor of the bi-material. The study provides a faster calculation method and has important implications for solving interfacial angular dislocation problems.
PHILOSOPHICAL MAGAZINE
(2024)
