Quantum control of dispersion in electromagnetically induced transparency via interacting dressed ground states

Abstract

We offer a general treatment of electromagnetically induced transparency (EIT) in a five level system consisting of four metastable ground states. Two additional RF/microwave fields coherently couple the two ground states of the standard EIT Λ atom to a pair of additional hyperfine states in the ground state manifold, generating two sets of dressed states that interact via the probe and control lasers, which couple to the electronic excited state. These new hyperfine dressed states manifest themselves in the linear optical susceptibility of the probe as new resonances in addition to the Autler-Townes doublet characteristic of EIT. In particular, we show that the existence of two new narrow resonances, whose width are limited only by ground state decoherence, appear inside the normal EIT transparency window. We show that by controlling the intensity of these RF/microwave fields, one can engineer both the position and width of these narrow resonances and thereby exercise additional control over both the dispersion and group velocity of the probe.

Radio-frequency-assisted electromagnetically induced transparency

“…We show that the full spectrum includes nonlinear resonances, analogous to the sidebands in the Mollow triplet [16], and explain the sidebands with a dressed state model for the rf coupled dark state. We also confirm the predicted resonance narrowing [10].…”

“…The strength of the linear EIT resonance is controlled by the sum of the squared products of the |1,N and |2,N amplitudes in (10) and (11), weighted by the respective reduced population i in the bare dressed state, (sin β cos β) 2 1 and (− sin β cos β) 2 2 .…”

“…[10][11][12][13], it is enlightening to find simple models for the rf phase response. For this purpose we define the R 0 dark state at a fixed position z, in the absence of an rf field,…”

“…Theory has predicted new narrow resonances, limited in width only by the ground-state decoherence, with the prospect of engineering both the position and width of the narrow resonances by rf amplitude, frequency and phase, thus promising intimate control over dispersion and group velocity [2,[10][11][12].…”

Electromagnetically Induced Transparency in a Double Well Atomic Josephson Junction

“…Transitions from the {|B , |B } manifold to |a 0 will then exhibit absorption resonances at ω a − ω B,B , which correspond to the new ultranarrow features. All in all there are six transitions that should appear as resonances in the absorption spectrum corresponding to transitions from {|B , |B } dressed manifold to {|a + , |a − , |a 0 } states via the probe [11]. The transitions to the two "bright" states |a ± correspond to the main absorption peaks lo-…”