Olshanii, Maxim

Date:  Thursday, February 9, 2017
Time: 11:00
Place: ETH Zurich, Hönggerberg, Room HIT J 51
Host: Tilman Esslinger

Quantum Galilean Cannon as a Schrodinger Cat

Maxim Olshanii
University of Massachusetts Boston, USA

In this presentation we show that a quantum few-body system with a properly tuned set of masses is capable of evolving from a disentangled state to a state where the heavy particles are entangled with the light ones. Here, we focus on the so-called Galilean Cannon: a one-dimensional sequence of N hard-core particles in a ratio 1 : 1/3 : 1/6 : 1/10 : ... : 2/N(N+1) interacting with a hard wall. In this system, nontrivial conservation laws associated with a reflection group of an N-dimensional regular tetrahedron protect the evolution from both classical stochastization and quantum diffraction. In one of the examples, the Renyi entropy increases from zero in the beginning of the evolution to almost ln(2) in the end. We consider specie-alternating mutually repulsive bosonic soliton trains as an empirical realization of the scheme. We finally suggest a concrete way to exploit the heavy-light entanglement by proposing a quantum atomic sensor containing N_atoms atoms whose sensitivity is \sqrt{N} higher than the one for a one-atom sensor with signal-to-noise reduced after N_{atoms} repetitions. Another attractive feature of this device is that it circumvents completely the usual difficulty in realizing beam-splitting of massive objects: in our scheme, the beamsplitter acts only on a single light particle, who is subsequently entangled with the heavy via robust processes only.

In collaboration with Thibault Scoquart, Vanja Dunjko, Dmitry Yampolsky, and Steven Glenn Jackson.

Supported by the NSF, ONR and IFRAF. TS's was supported by the École Normale Supérieure.