Large array of Schrödinger cat states facilitated by an optical waveguide

Abstract

Quantum engineering using photonic structures offer new capabilities for atom-photon interactions for quantum optics and atomic physics, which could eventually lead to integrated quantum devices. Despite the rapid progress in the variety of structures, coherent excitation of the motional states of atoms in a photonic waveguide using guided modes has yet to be demonstrated. Here, we use the waveguide mode of a hollow-core photonic crystal fibre to manipulate the mechanical Fock states of single atoms in a harmonic potential inside the fibre. We create a large array of Schrödinger cat states, a quintessential feature of quantum physics and a key element in quantum information processing and metrology, of approximately 15000 atoms along the fibre by entangling the electronic state with the coherent harmonic oscillator state of each individual atom. Our results provide a useful step for quantum information and simulation with a wide range of photonic waveguide systems.

A Versatile Quantum Simulator for Coupled Oscillators Using a 1D Chain of Atoms Trapped near an Optical Nanofiber

“…In contrast to quantum simulation with ions [31,32], we can even turn off the interactions between arbitrary pairs of particles. In the second part, we describe the oscillator states as qubits and use this approach to design quantum gates [33,34] or produce entangled states [35][36][37].…”

Quantum state engineering using weak measurement

“…There have plenty of research works studied various quantum states and proposed the schemes for generating them. The particular interests has been devoted to Fock states [7][8][9], Schrodinger cat states [10][11][12][13][14][15][16][17][18] , squeezed states [19], photon number states [20][21][22][23][24][25][26], binomial states [27][28][29][30], and squeezed state excitations [31][32][33][34]. Another interesting class of nonclassical states such as photonadded coherent states [35], photon-subtracted or -added squeezed states [36] that have been a subject of interest since they also have potential applications in many related quantum information processing [37][38][39][40].…”

Quantum Oscillator Noise Spectroscopy via Displaced Cat States

“…In this Letter, we experimentally demonstrate a method for the spectrally resolved sensing of harmonic oscillator frequency fluctuations that is based on the interference of cat states [18]. The deterministic generation of oscillator cat states has been demonstrated in a variety of systems [19][20][21][22][23], and interference of the oscillator wave packets has previously been applied to single photon detection [24]. Here, we apply a continuously driven qubit-state-dependent displacement to the motional wave packet of a single trapped ion, while inverting the drive phase at regular intervals to tune the protocol's peak sensitivity in frequency space.…”