Probing quantum criticality of a measurement-induced phase transition with alkaline earth Rydberg at
Abstract
Open many-body systems are ubiquitous in quantum engineering, and the balance of internal entanglement dynamics against decoherence, from interactions with the environment is at the heart of modern quantum information science. These interactions with the environme,nt constitute a quantum measurement, which is an irreversible process where quantum coherence in the system is converted to classica,l entropy in the measurement apparatus due to intrinsic quantum randomness. In quantum engineering, interactions with the environmen,t are a tool, via measurement, that enables, e.g.,quantum error correction, heralded entanglement generation, and even the creation, of collective states relevant for metrology. However, interactions with the environment are also a major impediment, via decoherenc,e, that limits the circuit depth of large-scale quantum processors, the achievable correlation length in quantum simulations, the in,terrogation time of quantum sensors, and the physical length scale of quantum networks.It is therefore essential to understand the d,ynamics of open many-body systems to realize the full potential of myriad quantum technologies. The rise of programmable quantum dev,ices has motivated the exploration of circuit models that incorporate quantum measurements to ad,uingly, new classes of quantum phase transitions have been predicted in random quantum circuits by varying the coupling strength to, the environment through measurement, and are referred to as measurement-induced phase transitions (MPTs). Recently, the MPT has b,een observed in a small-scale trapped ion experiment, but the universality and critical behavior of the transition remains out of re,ach due to the required system size scaling to approximately 40 qubits.Here, we propose to explore large random circuits that exhibi,t MPTs with alkaline earth Rydberg atom arrays. By encoding quantum information in the highly-coherent nuclear spin-1/2 system of yt,terbium-171 (Yb-171), we construct an atomic systemthat contains both a computational qubit hosted in the metastable clock state a,nd an auxiliary qubit hosted in the absolute ground state. The auxiliary qubit can be used for robust single-qubit mid-circuit measu,rements an essential component of the MPT-containing circuits and we propose a novel protocol to realize these single-qubit meas,urements with only global pulses. Crucially, the flexibility and scalability of the atom array platform allows us to probe the quant,um criticality of the MPT for the first time, shedding new light on the nature of this phenomena and its effects on large-scale syst,ems beyond classical tractability. This work establishes alkaline earth Rydberg atom arrays as a powerful new toolbox for programmab,le many-body systems with tunable dissipation a fundamental topic at the intersection of quantum optics, many-body physics, and qu,antum error correction.This work extends the capabilities of alkaline earth atoms already widely used for precision optical atomic, clocks to include quantum computation and quantum communication. The confluence of these areas optical clocks capable of progra,mmable quantum circuits and networking protocols shows great promise for quantum-enhanced and distributed sensing (of electromagnet,ic fields and geodesy) and timekeeping. For example, it could provide alternative positioning, navigation, and timing options that c,ead to significant improvements in submarine detection and, in turn, compromise the survivability of sea-based nuclear deterrents. T,his effort will also aid in the development of large-scale algorithms for quantum cryptography.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Apr 01, 2022
- Source ID
- N000142212311
Entities
People
- Jacob P Covey
Organizations
- Office of Naval Research
- United States Navy
- University of Illinois Urbana–Champaign