Kavli Affiliate: Archana Raja| Summary:The simple electrostatic picture of a trion is that of an excess charge inducing an exciton polarization and binding closer (farther) to the hole (electron) side of it. Trion formation can be forbidden when such spontaneous rearrangement of charges is not allowed by the application of external perturbation, such as electric […]
Kavli Affiliate: Carlos Bustamante | Summary:The ability to predict protein three-dimensional structures from amino acid sequences is a landmark achievement in molecular biology, where recent deep learning approaches such as AlphaFold are the culmination of decades of work. Yet, the quantitative understanding of how protein sequences give rise to dynamic conformational changes and higher-order assemblies […]
Kavli Affiliate: Gerbrand Ceder| Summary:Electrochemically redox-active halide (eREAL) materials are an emerging class of materials that combine high Li-ion conductivity with transition-metal redox activity, making them promising candidates for cathode or catholyte applications. As a redox-active catholyte, they could significantly increase the energy density of solid-state batteries. In this work, we perform first-principles calculations on […]
Kavli Affiliate: James Analytis| Summary:The unconventional superconductor 4Hb-TaS$_2$ is a natural heterostructure that can be broadly understood as interleaving Mott-like and metallic layers. We study the properties of this material as a function of quenched disorder in the form of Se/S substitution and find that while disordered samples show bulk superconductivity, clean samples do not. […]
Kavli Affiliate: Birgitta Whaley | Summary:Quantum circuit ensembles that have the properties of unitary k-designs represent applications where there is no obvious bias toward any particular Pauli support, as is the case in simulating systems exhibiting ”quantum chaos,” which range from quantum dynamics near black holes to gapless spin fluid analysis. However, noisy hardware makes […]
Kavli Affiliate: Birgitta Whaley | Summary:The Non-Orthogonal Quantum Eigensolver (NOQE) provides an accurate framework for electronic-structure calculations, but the estimation of its Hamiltonian and overlap matrix elements relies on sampling and requires $O(1/varepsilon^2)$ circuit repetitions to achieve additive precision $varepsilon$. Here, we reformulate this matrix-element estimation step as a collection of amplitude-estimation tasks and integrate […]
Kavli Affiliate: James Analytis| Summary:Understanding if low-energy excitations can remain itinerant in the presence of strong disorder remains a central challenge in frustrated quantum magnets, where disorder is generally expected to localize excitations through Anderson-like mechanisms. Here we report the emergence of charge-neutral itinerant excitations in a van der Waals compound Cr$_3$Se$_2$Br$_5$, a strongly disordered […]
Kavli Affiliate: Felix Fischer | Summary:We study a family of Jacobi operators in which the diagonal entries are multiplied by a coupling parameter $λgeq0$. Under suitable conditions, the operator is self-adjoint for every $λ>0$, while the formal limit at $λ=0$ is a symmetric Jacobi operator admitting a one-parameter family of self-adjoint extensions. A central ingredient […]
Kavli Affiliate: Joel Moore | Summary:Periodically driven quantum many-body systems can spontaneously break discrete time-translation symmetry, realizing discrete time crystals. To date, both experimental and theoretical efforts have largely focused on the simplest case of spontaneous period-doubling in $mathbbZ_2$ discrete time crystals realized with qubits. This owes, in part, to the challenge of stabilizing eigenstate […]
Kavli Affiliate: Michael Crommie | Summary:We directly visualize a two-dimensional anisotropic Wigner crystal and its quantum melting in monolayer 1T-ReSe2 using non-invasive scanning tunnelling microscopy. In crystals with anisotropic effective mass, an electron’s quantum wavefunction becomes elongated along the light-mass direction to reduce kinetic energy. At low electron density, such anisotropic electrons are predicted to […]