Dispersive Photon Blockade in a Superconducting Circuit

Abstract

Mediated photon-photon interactions are realized in a superconducting coplanar waveguide cavity coupled to a superconducting charge qubit. These nonresonant interactions blockade the transmission of photons through the cavity. This so-called dispersive photon blockade is characterized by measuring the total transmitted power while varying the energy spectrum of the photons incident on the cavity. A staircase with four distinct steps is observed and can be understood in an analogy with electron transport and the Coulomb blockade in quantum dots. This work differs from previous efforts in that the cavity-qubit excitations retain a photonic nature rather than a hybridization of qubit and photon and provides the needed tolerance to disorder for future condensed matter experiments.

Multiphoton blockades in pulsed regimes beyond stationary limits

“…An analogous phenomenon of phonon blockade was predicted for an artificial superconducting atom coupled to a nanomechanical resonator [23], as well as the polariton blockade effect due to polariton-polariton interactions has been considered in [24]. Recently, PB was considered in dispersive qubit-field interactions in a superconductive coplanar waveguide cavity [25] and with time-modulated input [26].…”

Fate of photon blockade in the deep strong-coupling regime

“…The photon blockade results in a highly nonclassical emission of photons from the cavity, characterized by a strong antibunching. The photon blockade has been investigated theoretically and experimentally in a large variety of systems, such as atomic cavity QED [10,11], semiconductor nanostructures [12,13] and superconducting circuits [14][15][16].…”

Measurement of many-body chaos using a quantum clock

“…In addition, one can introduce strong optical nonlinearity to the local cavities, by embedding qubits into it. In this case, the photons in the cavities can be thought as hard-core bosons due to photon blockade [15,23], i.e. b 2 j = b †2 j = 0, as long as the nonlinearity is much larger than the effective hopping strength between the resonators, g 2 b /∆ b .…”

“…Specifically, we consider a 2D on-chip circuit-QED quantum simulator consisting of hybrid resonator-qubit network, pioneered by a series of proposals, experiments [21][22][23][24][25][26][27]43]. As schematically shown in Fig.…”

“…From an experimental standpoint, our protocol is motivated by the rapid development of quantum simulation and information technology in recent years, such as cavity quantum electrodynamics (QED) [15][16][17][18], circuit-QED [19][20][21][22][23][24][25][26][27][28], Rydberg atoms [29][30][31][32], and trapped ions [33]; it is within current technology to engineer an ancilla qubit coupled to a manybody system globally. The ancilla qubit can be either the cavity photon mode or the internal state of an atom.…”