Advances in quantum control of three‐level superconducting circuit architectures

Abstract

Advanced control in Lambda (Λ) scheme of a solid state architecture of artificial atoms and quantized modes would allow the translation to the solid‐state realm of a whole class of phenomena from quantum optics, thus exploiting new physics emerging in larger integrated quantum networks and for stronger couplings. However control solid‐state devices has constraints coming from selection rules, due to symmetries which on the other hand yield protection from decoherence, and from design issues, for instance that coupling to microwave cavities is not directly switchable. We present two new schemes for the Λ‐STIRAP control problem with the constraint of one or two classical driving fields being always‐on. We show how these protocols are converted to apply to circuit‐QED architectures. We finally illustrate an application to coherent spectroscopy of the so called ultrastrong atom‐cavity coupling regime.

Optimization of STIRAP-based state transfer under dissipation

“…STIRAP was introduced more than two decades ago for population transfer in Λ-type atoms [1]. Due to the advantages of being robust, simple, and efficient, this approach, as well as its theoretical extensions [2][3][4][5][6][7][8][9], have found applications in a variety of physical systems for different tasks (see e.g. [10][11][12][13][14][15][16][17][18] and for a most recent review, see [19]).…”

Speedup of Adiabatic Multiqubit State-Transfer by Ultrastrong Coupling of Matter and Radiation

“…This feature is reminiscent to what happens in a protocol called hyperstirap [12], where efficiency can be further increased by a proper phase modulation [14] of the control. Therefore it can be foreseen that optimal control techniques [24,25] could further improve the fidelity of such operations, also exploiting coupling schemes based on modulation of detunings [26,19].…”

Photon pair production by STIRAP in ultrastrongly coupled matter-radiation systems

“…1b) for suitable choice of the frequencies ω k . For not too large g ω c = , the dynamics is captured by a simplified three-level model [19] described by the following Hamiltonian in the rotating frame…”