A5017412394- Quantum Information and Cryptography
- Mechanical and Optical Resonators
- Quantum and electron transport phenomena
- Quantum optics and atomic interactions
- Cold Atom Physics and Bose-Einstein Condensates
- Photonic and Optical Devices
- Advanced MEMS and NEMS Technologies
- Quantum Computing Algorithms and Architecture
- Neural Networks and Reservoir Computing
- Topological Materials and Phenomena
- Quantum many-body systems
- Quantum Mechanics and Non-Hermitian Physics
- Physics of Superconductivity and Magnetism
- Atomic and Subatomic Physics Research
- Surface and Thin Film Phenomena
- Strong Light-Matter Interactions
Beijing University of Technology
2019-2025
Institute of Physics
2017-2020
University of Chinese Academy of Sciences
2017-2020
Chinese Academy of Sciences
2017-2019
Tsinghua University
2013-2018
Institute of Microelectronics
2013-2018
We propose an efficient method to generate entangled states of vibrational modes membranes which are coupled a single-mode cavity field via the radiation pressure. By using sideband excitations, we show that arbitrary in different can be produced principle by sequentially applying series classical pulses with desired frequencies, phases, and durations. As examples, how synthesize several typical states, such as Bell NOON Greenberger-Horne-Zeilinger W states. The environmental effect,...
We propose to manipulate the statistic properties of photons transport nonreciprocally via quadratic optomechanical coupling. present a scheme generate interactions in normal optical modes whispering-gallery-mode (WGM) system by eliminating linear couplings anticrossing different modes. By optically pumping WGM one direction, effective coupling that direction will be enhanced significantly, and nonreciprocal photon blockade observed consequently. Our proposal has potential applications for...
We propose a theoretical scheme of using two fixed-frequency resonator couplers to tune the interaction between Xmon qubits. The indirect qubits induced by resonators can cancel each other, so direct qubit-qubit coupling is not essential for switching off. So, we suppress static ZZ with weak and even eliminate through destructive interferences double-path couplers. cross-Kerr resonance induce additional poles which should be kept away during two-qubit gates. double-resonator could unfreeze...
Abstract The engineering of quantum devices has reached the stage where we now have small-scale processors containing multiple interacting qubits within them. Simple circuits been demonstrated and scaling up to larger numbers is underway. However, as number in these increases, it becomes challenging implement switchable or tunable coherent coupling among typical approach detune each qubit from others bus connected to, but increases this problematic achieve practice due frequency crowding...
Besides the conventional transverse couplings between superconducting qubits (SQs) and electromagnetic fields, there are additional longitudinal when inversion symmetry of potential energies SQs is broken. We study nonclassical-state generation in a SQ which driven by classical field coupled to single-mode microwave field. find that can induce transitions two energy levels SQs, either generate or annihilate, controllable way, different photon numbers cavity The effective Hamiltonians these...
We propose an implementation of a generalized Su-Schrieffer-Heeger (SSH) model based on optomechanical arrays. The topological properties the SSH depend effective interactions which can be controlled by strong driving fields. Three phases including one trivial and two distinct are found in model. phase transition observed turning strengths via adjusting Moreover, four types edge states created open chain under single-particle excitation, dynamical behaviors excitation related to periodic...
It has been shown that there are not only transverse but also longitudinal couplings between microwave fields and a superconducting qubit with broken inversion symmetry of the potential energy. Using multiphoton processes induced by coupling frequency matching conditions, we design universal algorithm to produce arbitrary superpositions two-mode photon states in two separated transmission line resonators, which coupled qubit. Based on our algorithm, analyze generation evenly-populated NOON...
Using different configurations of applied strong driving and weak probe fields, we find that only a single three-level superconducting quantum circuit (SQC) is enough to realize amplification, attenuation, frequency conversion microwave fields. Such SQC has possess $\mathrm{\ensuremath{\Delta}}$-type cyclic transitions. Different from the parametric amplification (attenuation) in nonlinear optical media, real energy levels are involved exchange when these processes completed. We...
We propose a scheme of tunable coupler based on quarter-wave resonator for scalable quantum integrated circuits. The open end the T-type is capacitively coupled to two Xmon qubits, while another an asymmetric dc-SQUID which dominates inductive energy resonator. dc-Current applied through flux bias line could change magnetic inside dc-SQUID, so frequency can be effectively tuned and qubit-qubit coupling totally switched off. As increase junction asymmetry SQUID's effective phase difference...
Stimulated emission and absorption are two fundamental processes of light–matter interaction, the coefficients should be equal. However, we will describe a generic method to realize significant difference between stimulated nondegenerate energy levels, which refer as nonreciprocal transition. As simple implementation, cyclic three-level atom system, comprising levels one auxiliary level, is employed show transition via combination synthetic magnetism reservoir engineering. Moreover,...
The engineering of quantum devices has reached the stage where we now have small scale processors containing multiple interacting qubits within them. Simple circuits been demonstrated and scaling up to larger numbers is underway. However as number in these increases, it becomes challenging implement switchable or tunable coherent coupling among typical approach detune each qubit from others bus connected to, but increases this problematic achieve practice due frequency crowding issues. Here,...
We propose to generate localized artificial magnetic fields using two thin Raman laser beams intersected at a narrow region of two-leg ladder, where the frequency difference must approximately match energy offset between legs. Based on this method, we investigate single-atom transport in ladder with only rungs, which, together legs, enclose flux. Here, atoms legs (channels) possess different onsite energies that produce another offset. find atom incoming from left channel can experience...
We propose to periodically modulate the onsite energy via two-tone drives, which can be furthermore used engineer artificial gauge potential. As an example, we show that fermionic ladder model penetrated with effective magnetic flux constructed by superconducting qubits using such two-tone-drive-engineered In this system, single-particle ground state range from vortex phase Meissner due competition between interleg coupling strength and flux. also present method experimentally measure chiral...
With a high-loss resonator supplying the non-Hermiticity, we study Energy level degeneracy and quantum state evolution in tunable coupling superconducting circuit. The qubit's effective energy damping rate can be continually tuned circuit, positions numbers of degenerate points are controllable. efficient exchange asymmetry with non-hermitian nonreciprocal between two qubits. controllable non-Hermiticity provides new insights methods for exploring unconventional effects
We propose a theoretical scheme to realize the controllable non-Hermitian qubit–qubit coupling by adding high-loss resonator in tunable superconducting quantum circuit. By changing effective coupling, phase and amplitude of resonator–qubit interaction, qubits’ states, we can continually tune energy level attraction, position EP (exceptional point), non-reciprocity The EPs affect states’ evolutions exchange efficiencies for two qubits non-reciprocal interactions between provide new insights...
We theoretically study photon transmission and mechanical ground state cooling in a two-dimensional optomechanical system that is formed of suspended graphene sheet on an one-dimensional crystal. When the frequencies resonator nanobeam resonator(phononic mode crystal) are approximately same, $\Lambda$-type degenerate four-level optomechanics shows two-color optomechanically-induced transparency , window could be switched among probe signal's absorption, transparency, amplification. According...
Abstract We investigate the transport problem that a spinful matter wave is incident on strong localized spin-orbit-coupled Bose-Einstein condensate in optical lattices, where localization admitted by atom interaction only existing at one particular site, and spin-orbit coupling arouse spatial rotation of spin texture. find tuning orientation can lead to spin-nonreciprocal/spin-reciprocal transport, meaning properties are dependent on/independent waves. In former case, we obtain conditions...
In this paper, we study the transport properties of quantum states in square-lattice bit model by using inductive couplers to generate artificial gauge potential (effective magnetic flux). It is found theoretical calculation that eigenstates single particle and hole have same eigen energy spectrum, average currents, sinusoidally modulated effective flux, are opposite each other with respect energy. For an initial single-particle or single-hole state where only one lattice site occuplied, if...
We investigate the transport problem that a spinful matter wave is incident on strong localized spin-orbit-coupled Bose-Einstein condensate in optical lattices, where localization admitted by atom interaction only existing at one particular site, and spin-orbit coupling arouse spatial rotation of spin texture. find tuning orientation can lead to spin-nonreciprocal / spin-reciprocal transport, meaning properties are dependent independent waves. In former case, we obtain conditions achieve...