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We propose a polynomial-time algorithm for simulation of the class of pairing Hamiltonians, e.g., the BCS Hamiltonian, on an NMR quantum computer. The algorithm adiabatically finds the low-lying spectrum in the vicinity of the gap between…

Quantum Physics · Physics 2009-11-07 L. -A. Wu , M. S. Byrd , D. A. Lidar

Bremsstrahlung emission in collisions between charged nuclei is equivalent to nuclear gamma decay between continuum states. The way the continuum spectrum can be treated is not unique, and efficiency and accuracy of cross section…

Nuclear Theory · Physics 2014-07-22 E. Garrido , A. S. Jensen , D. V. Fedorov

Quantum channels describe the most general dynamics of open quantum systems. A quantum channel, as a linear map on vectorized quantum states, can be represented by a single matrix, whose spectrum is called the channel spectrum. Here we…

Quantum Physics · Physics 2026-01-28 Yuan-De Jin , Wen-Long Ma

Composite fermion (CF) is a topological quasiparticle that emerges from a non-perturbative attachment of vortices to electrons in strongly correlated two-dimensional materials. Similar to non-interacting fermions that form Landau levels in…

Mesoscale and Nanoscale Physics · Physics 2024-08-19 Songyang Pu , Ajit C. Balram , Yuwen Hu , Yen-Chen Tsui , Minhao He , Nicolas Regnault , Michael P. Zaletel , Ali Yazdani , Zlatko Papić

Generating large, non-trivial quantum chemistry test problems with known ground-state solutions remains a core challenge for benchmarking electronic structure methods. Inspired by planted-solution techniques from combinatorial optimization,…

Quantum Physics · Physics 2025-09-23 Linjun Wang , Joshua T. Cantin , Smik Patel , Ignacio Loaiza , Rick Huang , Artur F. Izmaylov

The interaction of a five-level atomic system involving electromagnetically induced transparency with four light fields is investigated. Two different light-atom configurations are considered, and their efficiency in generating large…

Optics · Physics 2009-11-11 Carlo Ottaviani , Stojan Rebic , David Vitali , Paolo Tombesi

We analyze, in general terms, the evolution of energy levels in quantum mechanics, as a function of a coupling parameter, and demonstrate the possibility of level crossings in systems described by irreducible matrices. In long-range…

Quantum Physics · Physics 2017-02-15 C. M. Adhikari , V. Debierre , U. D. Jentschura

We use machine learning to classify rational two-dimensional conformal field theories. We first use the energy spectra of these minimal models to train a supervised learning algorithm. We find that the machine is able to correctly predict…

Strongly Correlated Electrons · Physics 2021-07-13 En-Jui Kuo , Alireza Seif , Rex Lundgren , Seth Whitsitt , Mohammad Hafezi

We perform a Hartree-Fock calculation in order to describe the ground state of a vertical double quantum dot in the absence of magnetic fields parallel to the growth direction. Intra- and interdot exchange interactions determine the singlet…

Mesoscale and Nanoscale Physics · Physics 2009-11-07 David Sanchez , L. Brey , Gloria Platero

The objective of this article is to give an effective algebraic characterization of normal crossing hypersurfaces in complex manifolds. It is shown that a hypersurface has normal crossings if and only if it is a free divisor, has a radical…

Algebraic Geometry · Mathematics 2018-05-04 Eleonore Faber

We introduce a simple two-level boson model with the same energy surface as the Q-consistent Interacting Boson Model Hamiltonian. The model can be diagonalized for large number of bosons and the results used to check analytical finite-size…

Nuclear Theory · Physics 2007-05-23 J. Vidal , J. M. Arias , J. Dukelsky , J. E. Garcia-Ramos

We establish a hierarchical ordering of periodic orbits in a strongly coupled multidimensional Hamiltonian system. Phase space structures can be reconstructed quantitatively from the knowledge of periodic orbits alone. We illustrate our…

Chaotic Dynamics · Physics 2007-05-23 S. Gekle , J. Main , T. Bartsch , T. Uzer

The density matrix of a two-level system (spin, atom) is usually determined by measuring the three non-commuting components of the Pauli vector. This density matrix can also be obtained via the measurement data of two commuting variables,…

Quantum Physics · Physics 2012-05-25 B. Mehmani , A. E. Allahverdyan , Th. M. Nieuwenhuizen

We derive a simple formula for the transformation of an arbitrary covariance matrix of (n+2) bosonic modes under general Bell-like detections, where the last two modes are combined in an arbitrary beam splitter (i.e., with arbitrary…

Quantum Physics · Physics 2014-10-13 Gaetana Spedalieri , Carlo Ottaviani , Stefano Pirandola

Solving for the lowest energy eigenstate of the many-body Schrodinger equation is a cornerstone problem that hinders understanding of a variety of quantum phenomena. The difficulty arises from the exponential nature of the Hilbert space…

The so-called equation of motion method is useful to obtain the explicit form of the eigenvectors and eigenvalues of certain non self-adjoint bosonic Hamiltonians with real eigenvalues. These operators can be diagonalized when they are…

Quantum Physics · Physics 2015-09-03 Natalia Bebiano , Joao da Providencia , Joao P. da Providencia

Transfer matrix techniques are used to provide a new proof of Widom's results on the asymptotic spectral theory of finite block Toeplitz matrices. Furthermore, a rigorous treatment of the skin effect, spectral outliers, the generalized…

Mathematical Physics · Physics 2024-10-08 Lars Koekenbier , Hermann Schulz-Baldes

The diagonalization of matrices may be the top priority in the application of modern physics. In this paper, we numerically demonstrate that, for real symmetric random matrices with non-positive off-diagonal elements, a universal scaling…

Quantum Physics · Physics 2020-11-06 Wei Pan , Jing Wang , Deyan Sun

We present a new pseudospectral algorithm for the calculation of the structure of atoms in strong magnetic fields. We have verified this technique for one, two and three-electron atoms in zero magnetic fields against laboratory results and…

Atomic Physics · Physics 2015-05-13 Jeremy S. Heyl , Anand Thirumalai

The task of estimating the ground state of Hamiltonians is an important problem in physics with numerous applications ranging from solid-state physics to combinatorial optimization. We provide a hybrid quantum-classical algorithm for…

Quantum Physics · Physics 2022-02-28 Kishor Bharti , Tobias Haug