Complexity of spin configuration dynamics due to unitary evolution and periodic projective measurements.

We study the Hamiltonian dynamics of a many-body quantum system subjected to periodic projective measurements, which leads to probabilistic cellular automata dynamics. Given a sequence of measured values, we characterize their dynamics by performing a principal component analysis (PCA). The number of principal components required for an almost complete description of the system, which is a measure of complexity we refer to as PCA complexity, is studied as a function of the Hamiltonian parameters and measurement intervals.

Relaxation Exponents of OTOCs and Overlap with Local Hamiltonians.

OTOC has been used to characterize the information scrambling in quantum systems. Recent studies have shown that local conserved quantities play a crucial role in governing the relaxation dynamics of OTOC in non-integrable systems. In particular, the slow scrambling of OTOC is seen for observables that have an overlap with local conserved quantities.

Digital Quantum Simulation of the Spin-Boson Model under Markovian Open-System Dynamics.

Digital quantum computers have the potential to simulate complex quantum systems. The spin-boson model is one of such systems, used in disparate physical domains. Importantly, in a number of setups, the spin-boson model is open, i.

An exopolysaccharide from Leuconostoc mesenteroides showing interesting bioactivities versus foodborne microbial targets.

An exopolysaccharide (EPS_B3) produced by a Leuconostoc mesenteroides strain isolated from a semi-hard Italian cheese was chemically and biologically characterized. HPLC-SEC, NMR, FT-IR and monosaccharide composition experiments were performed. Antimicrobial, antibiofilm, bifidogenic, antioxidant, and DNA-protective activity of EPS_B3 were also studied.

Transport and spectral properties of the XX+XXZ diode and stability to dephasing.

We study the transport and spectral property of a segmented diode formed by an XX+XXZ spin chain. This system has been shown to become an ideal rectifier for spin current for large enough anisotropy. Here we show numerical evidence that the system in reverse bias has signatures pointing toward the existence of three different transport regimes depending on the value of the anisotropy: ballistic, diffusive, and insulating.

Thermodynamic performance of a periodically driven harmonic oscillator correlated with the baths.

We consider a harmonic oscillator under periodic driving and coupled to two harmonic-oscillator heat baths at different temperatures. We use the thermofield transformation with chain mapping for this setup, which allows us to study the unitary evolution of the system and the baths up to a time when the periodic steady state emerges in the system. We characterize this periodic steady state, and we show that, by tuning the system and the bath parameters, one can turn this system from an engine to an accelerator or even to a heater.

Turbidimetric definition of growth limits in probiotic Lactobacillus strains from the perspective of an adaptation strategy.

The application of an adaptation strategy for probiotics, which may improve their stress tolerance, requires the identification of the growth range for each parameter tested. In this study, 4 probiotics (Lactobacillus acidophilus, Lacticaseibacillus casei, Lacticaseibacillus rhamnosus, and Lactiplantibacillus plantarum) were grown under different pH, NaCl, and sucrose concentrations at 25°C, 30°C, and 37°C. Turbidimetric growth curves were carried out and lag phase duration, maximum growth rate, and amplitude (i.

Timing of elective tracheotomy and duration of mechanical ventilation among patients admitted to intensive care with severe COVID-19: A multicenter prospective cohort study.

Background: Optimal timing for tracheotomy for critically ill COVID-19 patients requiring invasive mechanical ventilation (IMV) is not established.

Methods: Multicenter prospective cohort including all COVID-19 patients admitted to intensive care units (ICUs) in 36 hospitals who required tracheotomy during first pandemic wave. With a target emulation trial framework, we studied the causal effects of early (7-10 days) versus late (>10 days) tracheotomy (LT) on time from tracheotomy to weaning, postoperative mortality, and tracheotomy complications.

Giant rectification in segmented, strongly interacting spin chains despite the presence of perturbations.

Balachandran et al. [Phys. Rev.

Localization-delocalization effects of a delocalizing dissipation on disordered XXZ spin chains.

The interplay between interaction, disorder, and dissipation has shown a rich phenomenology. Here, we investigate a disordered XXZ spin chain in contact with a bath which, alone, would drive the system toward a highly delocalized and coherent Dicke state. We show that there exist regimes for which the natural orbitals of the single-particle density matrix of the steady state are all localized in the presence of strong disorders, for either weak interaction or strong interaction.

Scheme for automatic differentiation of complex loss functions with applications in quantum physics.

The past few years have seen a significant transfer of tools from machine learning to solve quantum physics problems. Automatic differentiation is one standard algorithm used to efficiently compute gradients of loss functions for generic neural networks. In this work we show how to extend automatic differentiation to the case of complex loss function in a way that can be readily implemented in existing frameworks and which is compatible with the common case of real loss functions.

Quantum Monte Carlo Simulations of the 2D Su-Schrieffer-Heeger Model.

Over the past several years, a new generation of quantum simulations has greatly expanded our understanding of charge density wave phase transitions in Hamiltonians with coupling between local phonon modes and the on-site charge density. A quite different, and interesting, case is one in which the phonons live on the bonds, and hence modulate the electron hopping. This situation, described by the Su-Schrieffer-Heeger (SSH) Hamiltonian, has so far only been studied with quantum Monte Carlo in one dimension.

Giant Spin Current Rectification Due to the Interplay of Negative Differential Conductance and a Non-Uniform Magnetic Field.

In XXZ chains with large enough interactions, spin transport can be significantly suppressed when the bias of the dissipative driving becomes large enough. This phenomenon of negative differential conductance is caused by the formation of two oppositely polarized ferromagnetic domains at the edges of the chain. Here, we show that this many-body effect, combined with a non-uniform magnetic field, can allow for a high degree of control of the spin current.

Steady-state quantum transport through an anharmonic oscillator strongly coupled to two heat reservoirs.

We investigate the transport properties of an anharmonic oscillator, modeled by a single-site Bose-Hubbard model, coupled to two different thermal baths using the numerically exact thermofield based chain-mapping matrix product states (TCMPS) approach. We compare the effectiveness of TCMPS to probe the nonequilibrium dynamics of strongly interacting system irrespective of the system-bath coupling against the global master equation approach in Gorini-Kossakowski-Sudarshan-Lindblad form. We discuss the effect of on-site interactions, temperature bias as well as the system-bath couplings on the steady-state transport properties.

Transfer learning for scalability of neural-network quantum states.

Neural-network quantum states have shown great potential for the study of many-body quantum systems. In statistical machine learning, transfer learning designates protocols reusing features of a machine learning model trained for a problem to solve a possibly related but different problem. We propose to evaluate the potential of transfer learning to improve the scalability of neural-network quantum states.

Internal Delensing of Cosmic Microwave Background Polarization B-Modes with the POLARBEAR Experiment.

Using only cosmic microwave background polarization data from the polarbear experiment, we measure B-mode polarization delensing on subdegree scales at more than 5σ significance. We achieve a 14% B-mode power variance reduction, the highest to date for internal delensing, and improve this result to 22% by applying for the first time an iterative maximum a posteriori delensing method. Our analysis demonstrates the capability of internal delensing as a means of improving constraints on inflationary models, paving the way for the optimal analysis of next-generation primordial B-mode experiments.

General-Purpose Quantum Circuit Simulator with Projected Entangled-Pair States and the Quantum Supremacy Frontier.

Recent advances on quantum computing hardware have pushed quantum computing to the verge of quantum supremacy. Here, we bring together many-body quantum physics and quantum computing by using a method for strongly interacting two-dimensional systems, the projected entangled-pair states, to realize an effective general-purpose simulator of quantum algorithms. The classical computing complexity of this simulator is directly related to the entanglement generation of the underlying quantum circuit rather than the number of qubits or gate operations.

Thermalization with detailed-balanced two-site Lindblad dissipators.

The use of two-site Lindblad dissipators to generate thermal states and study heat transport was raised to prominence by Prosen and Žnidarič [J. Stat. Mech.

Energy Current Rectification and Mobility Edges.

We investigate how the presence of a single-particle mobility edge in a system can generate strong energy current rectification. Specifically, we study a quadratic bosonic chain subject to a quasiperiodic potential and coupled at its boundaries to spin baths of differing temperature. We find that rectification increases by orders of magnitude depending on the spatial position in the chain of localized eigenstates above the mobility edge.

Selective Decoupling and Hamiltonian Engineering in Dipolar Spin Networks.

We present a protocol to selectively decouple, recouple, and engineer effective interactions in mesoscopic dipolar spin networks. In particular, we develop a versatile protocol that relies upon magic angle spinning to perform Hamiltonian engineering. By using global control fields in conjunction with a local actuator, such as a diamond nitrogen vacancy center located in the vicinity of a nuclear spin network, both global and local control over the effective couplings can be achieved.

Heat current rectification in segmented XXZ chains.

We study the rectification of heat current in an XXZ chain segmented in two parts. We model the effect of the environment with Lindblad heat baths. We show that in our system, rectification is large for strong interactions in half of the chain and if one bath is at a cold enough temperature.

Transport and Energetic Properties of a Ring of Interacting Spins Coupled to Heat Baths.

We study the heat and spin transport properties in a ring of interacting spins coupled to heat baths at different temperatures. We show that interactions, by inducing avoided crossings, can be a means to tune both the total heat current flowing between the ring and the baths, and the way it flows through the system. In particular, we recognize three regimes in which the heat current flows clockwise, counterclockwise, and in parallel.

Perfect Diode in Quantum Spin Chains.

We study the rectification of the spin current in XXZ chains segmented in two parts, each with a different anisotropy parameter. Using exact diagonalization and a matrix product state algorithm, we find that a large rectification (of the order of 10^{4}) is attainable even using a short chain of N=8 spins, when one-half of the chain is gapless while the other has a large enough anisotropy. We present evidence of diffusive transport when the current is driven in one direction and of a transition to an insulating behavior of the system when driven in the opposite direction, leading to a perfect diode in the thermodynamic limit.

Injection Laryngoplasty Using Autologous Fat Enriched with Adipose-Derived Regenerative Stem Cells: A Safe Therapeutic Option for the Functional Reconstruction of the Glottal Gap after Unilateral Vocal Fold Paralysis.

Background: Paralysis of one vocal fold leads to glottal gap and vocal fold insufficiency that has significant impact upon a patient's quality of life. Fillers have been tested to perform intracordal injections, but they do not provide perdurable results. Early data suggest that enriching fat grafts with adipose-derived regenerative cells (ADRCs) promote angiogenesis and modulate the immune response, improving graft survival.