Dressed-state realization of the transition from electromagnetically induced transparency to Autler-Townes splitting in superconducting circuits

Abstract

We investigate electromagnetically induced transparency (EIT) and Autler-Townes splitting (ATS) in a driven three-level superconducting artificial system which is a dressed-state system resulting from the coupling of a superconducting charge qubit (an artificial atom) and a transmission line resonator. In the frame of the dressed-state approach and steady-state approximation, we study the linear absorption of the dressed artificial system to a weak probe signal in depth. In light of the spectrum-decomposition method and some other restrictions, we obtain the explicit conditions for the dressed-state realization of EIT and ATS and present a corresponding "phase diagram". In contrast to usual bare systems, these conditions given in the dressed system have an extra dependency on the qubit-resonator parameters. And by varying the qubit's Josephson coupling energy we demonstrate a transition from EIT to ATS.

Vacuum induced transparency and photon number resolved Autler-Townes splitting in a three-level system

“…Thus we study quantized-field-induced quantum interference and frequency shift, we here call them as VIT and vacuum induced ATS. Therefore, the cavity field in our study here and in 23 , 24 has very different purpose.…”

“…In their studies, both the classical control and probe fields are applied to the selected three-level system. The role of the cavity field in 23 , 24 is to assist the two-level system realizing a three-level system. These systems in 23 , 24 are still used to study a conventional EIT and ATS.…”

“…The role of the cavity field in 23 , 24 is to assist the two-level system realizing a three-level system. These systems in 23 , 24 are still used to study a conventional EIT and ATS. However, we here study a three-level system, in which two upper energy levels are coupled to a quantized single-mode cavity field, one and only one classical probe field is applied to the system.…”

“…Whereas, a dressed two-level system by a quantized field possesses many energy levels. Using a structure of three energy levels, chosen from many energy levels of dressed two-level systems by a quantized field 22 , both EIT and ATS have been theoretically studied 23 , 24 . Moreover, dressed two-level systems by quantized fields are also used to generate stimulated amplification 25 , demonstrate attenuation effects 26 , and exhibit polariton states with selective radiation spectrum 27 .…”

Enhancement of microwave squeezing via parametric down-conversion in a superconducting quantum circuit

“…Since the SQCs based on Josephson junctions can be designed and fabricated to tailor their characteristics for various purposes, they have also been used as the platforms for exploring quantum-optics phenomena in the microwave domain [19]. For instance, electromagnetically induced transparency and Autler-Townes splitting [22][23][24][25], sideband transitions [26,27],quantum entanglement [28][29][30][31][32][33], Bloch-Siegert shifts [34,35] and superradiant quantum phase transitions [36][37][38][39] were demonstrated using the SQCs. Also, the generation of squeezed microwaves via, e.g., degenerate fourwave mixing and degenerate PDC was proposed theoretically and later realized experimentally [40][41][42][43][44][45].…”