Coherent storage and manipulation of broadband photons via dynamically controlled Autler-Townes splitting

TL;DR

This paper demonstrates a novel method for broadband quantum memory using dynamically controlled Autler-Townes splitting, enabling efficient storage and manipulation of optical pulses with relaxed technical requirements.

Contribution

It introduces a protocol leveraging ATS for coherent light storage and manipulation, expanding the capabilities of quantum memory beyond traditional EIT-based methods.

Findings

Successfully stored and manipulated nanosecond optical pulses for up to a microsecond.

Demonstrated relaxation of technical requirements for quantum memory implementations.

Applicable to various platforms for quantum information and precision measurement.

Abstract

The coherent control of light with matter, enabling storage and manipulation of optical signals, was revolutionized by electromagnetically induced transparency (EIT), which is a quantum interference effect. For strong electromagnetic fields that induce a wide transparency band, this quantum interference vanishes, giving rise to the well-known phenomenon of Autler-Townes splitting (ATS). To date, it is an open question whether ATS can be directly leveraged for coherent control as more than just a case of "bad" EIT. Here, we establish a protocol showing that dynamically controlled absorption of light in the ATS regime mediates coherent storage and manipulation that is inherently suitable for efficient broadband quantum memory and processing devices. We experimentally demonstrate this protocol by storing and manipulating nanoseconds-long optical pulses through a collective spin state of laser-cooled Rb atoms for up to a microsecond. Furthermore, we show that our approach substantially relaxes the technical requirements intrinsic to established memory schemes, rendering it suitable for broad range of platforms with applications to quantum information processing, high-precision spectroscopy, and metrology.