arXiv subjects

Anurag

Publications and source records attributed to Anurag.

3 recordsLinked to original sources

arXiv2023

Observation of tunable discrete time crystalline phases

Discrete time crystals (DTCs) are emergent non-equilibrium phases of periodically driven many-body systems, with potential applications ranging from quantum computing to sensing and metrology. There has been significant recent interest in understanding mechanisms leading to DTC formation and a search for novel DTC phases beyond subharmonic entrainment. Here, we report observation of multiple DTC phases in a nanoelectromechanical system (NEMS) based on coupled graphene and silicon nitride membranes. We confirm the time-crystalline nature of these symmetry broken phases by establishing their many-body characters, long-range time and spatial order, and rigidity against parameter fluctuation or noise. Furthermore, we employ controlled mechanical strain to drive the transitions between phases with different symmetries, thereby mapping the emergent time-crystalline phase diagram. Overall, our work takes a step towards establishing time crystals as a system with complexity rivaling that of solid state crystals.

cond-mat.mes-hall↗

arXiv2017

A molecular-dynamics approach for studying the non-equilibrium behavior of x-ray-heated solid-density matter

When matter is exposed to a high-intensity x-ray free-electron-laser pulse, the x rays excite inner-shell electrons leading to the ionization of the electrons through various atomic processes and creating high-energy-density plasma, i.e., warm or hot dense matter. The resulting system consists of atoms in various electronic configurations, thermalizing on sub-picosecond to picosecond timescales after photoexcitation. We present a simulation study of x-ray-heated solid-density matter. For this we use XMDYN, a Monte-Carlo molecular-dynamics-based code with periodic boundary conditions, which allows one to investigate non-equilibrium dynamics. XMDYN is capable of treating systems containing light and heavy atomic species with full electronic configuration space and 3D spatial inhomogeneity. For the validation of our approach we compare for a model system the electron temperatures and the ion charge-state distribution from XMDYN to results for the thermalized system based on the average-atom model implemented in XATOM, an ab-initio x-ray atomic physics toolkit extended to include a plasma environment. Further, we also compare the average charge evolution of diamond with the predictions of a Boltzmann continuum approach. We demonstrate that XMDYN results are in good quantitative agreement with the above mentioned approaches, suggesting that the current implementation of XMDYN is a viable approach to simulate the dynamics of x-ray-driven non-equilibrium dynamics in solids. In order to illustrate the potential of XMDYN for treating complex systems we present calculations on the triiodo benzene derivative 5-amino-2,4,6-triiodoisophthalic acid (I3C), a compound of relevance of biomolecular imaging, consisting of heavy and light atomic species.

physics.atm-clus↗

arXiv2013

Low Power Dual Edge-Triggered Static D Flip-Flop

This paper enumerates new architecture of low power dual-edge triggered Flip-Flop (DETFF) designed at 180nm CMOS technology. In DETFF same data throughput can be achieved with half of the clock frequency as compared to single edge triggered Flip-Flop (SETFF). In this paper conventional and proposed DETFF are presented and compared at same simulation conditions. The post layout experimental results comparison shows that the average power dissipation is improved by 48.17%, 41.29% and 36.84% when compared with SCDFF, DEPFF and SEDNIFF respectively and improvement in PDP is 42.44%, 33.88% and 24.69% as compared to SCDFF, DEPFF and SEDNIFF respectively. Therefore the proposed DETFF design is suitable for low power and small area applications.

cs.OH↗