Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Physical Review A

Efficient nonlinear frequency mixing using Autler-Townes splitting

Hai‐Chao Li, Guo-Qin Ge, Muhammad Suhail Zubairy

Published Nov 2, 2020• 12 citations
Publisher

Abstract

Exploring enhanced nonlinear optics based on electromagnetically induced transparency (EIT) has always been one of the striking issues in cavity quantum electrodynamics. However, it is not clear whether the validity of EIT in enhancing nonlinear processes is universal. In this paper we demonstrate an efficient frequency conversion scheme via Autler-Townes splitting, instead of the so-called EIT mechanism, in a three-level quantum system. Because the selective system can be used to implement the conventional three-level EIT phenomenon, we present a direct evidence for the breakdown of nonlinear processes assisted by EIT. This strongly suggests that previously physical insight into the application of the standard EIT technique in nonlinear optics is not sufficient enough.

DOI
10.1103/physreva.102.053701

Related papers

High-efficiency four-wave mixing beyond pure electromagnetically induced transparency treatment

Hai‐Chao Li, Guo-Qin Ge, Muhammad Suhail Zubairy

We present a theoretical study of high-efficiency four-wave mixing (FWM) sum-frequency generation beyond a pure electromagnetically induced transparency (EIT) technique in a five-level atomic system. In our FWM scheme, with the assistance of two Λ-type subsystems utilized to create EIT and Autler-Townes splitting (ATS), a synergetic mechanism of EIT and ATS, or a dual-ATS mechanism is induced. These novel mechanisms can have a significant impact on the FWM process in the optically thick medium, and the FWM efficiency can be several orders of magnitude larger than that obtained from the pure EIT method. This Letter opens up a new perspective for exploring enhanced quantum nonlinear optical phenomena.

Optics Letters•Jul 9, 2019•10 citations

Evidence of Autler–Townes splitting in high-order nonlinear processes

Yanpeng Zhang, Zhiqiang Nie, Zhiguo Wang +3 more

We demonstrate Autler-Townes (AT) splitting of four-wave mixing in an electromagnetically induced transparency window, which results from the destructive interference between a three-photon process and a five-photon process. The primary and secondary AT splittings are achieved via induced atomic coherence in a four-level Y-type atomic system. Theoretical calculations fit well with the experimentally measured results. Such controlled multichannel splitting of nonlinear optical signals can have potential applications in optical communication and quantum information processing.

Optics Letters•Oct 11, 2010•67 citations

Mixture of Electromagnetically Induced Transparency and Autler–Townes Splitting in a Five-Level Atomic System*

Xiao-Yun 晓 芸 Zhang 张, Shan 山 Wu 吴, Hai‐Chao Li

Abstract Discerning electromagnetically induced transparency (EIT) from Autler–Townes splitting (ATS) is a significant issue in quantum optics and has attracted wide attention in various three-level configurations. Here we present a detailed study of EIT and ATS in a five-level atomic system considered to be composed of a four-level Y-type subsystem and a three-level Λ-type subsystem. In our theoretical calculations with standard density matrix formalism and steady-state approximation, we obtain the general analytical expression of the first-order matrix element responsible for the probe-field absorption. In light of the well-known three-level EIT and ATS criteria, we numerically show an intersection of EIT with ATS for the Y-type subsystem. Furthermore, we show that an EIT dip is sandwiched between two ATS dips (i.e., multi-dip mixture of EIT and ATS) in the absorption line for the five-level system, which can be explained by the dressed-state theory and Fano interference.

Communications in Theoretical Physics•Feb 1, 2017•3 citations

Electromagnetically induced transparency and Autler-Townes splitting: Two similar but distinct phenomena in two categories of three-level atomic systems

Tony Abi-Salloum

Electromagnetically induced transparency (EIT) and Autler-Townes (AT) splitting are two phenomena that could be featured in a variety of three-level atomic systems. The considered phenomena, EIT and AT, are similar ``looking'' in the sense that they are both characterized by a reduction in absorption of a weak field in the presence of a stronger field. In this paper, we explicitly set the threshold of separation between EIT and AT splitting in a unified study of four different three-level atomic systems. Two resonances are studied and compared in each case. A comparison of the magnitudes of the resonances reveals two coupling-field regimes and two categories of three-level system.

Physical Review A•May 19, 2010•159 citations

Difference‐Frequency Generation with and without Quantum Interference in Superconducting Circuits

Miao‐Xiang Liang, Hai‐Chao Li, Wei Xiong

Abstract Electromagnetically induced transparency (EIT) plays an important role in enhancing nonlinear optical processes at the quantum level. This paper proposes an accessible scheme for realizing high‐efficiency second‐order nonlinear difference‐frequency generation beyond the conventional EIT technique in superconducting circuits. By designing two subsystems to create two transparency windows from Autler–Townes splitting (ATS), a dual‐ATS mechanism is triggered in the scheme. This mechanism leads to an efficient difference‐frequency generation, and the efficiency obtained here can be four orders of magnitude larger than that of the EIT scheme. This study may pave a way for exploring ATS‐enhanced nonlinear optics.

Advanced Quantum Technologies•Jan 10, 2024•0 citations

Real-imaginary spectrum decomposition of the transparency spectra in microwave dressed Rydberg systems

Wenyu Niu, Lu Qin, Zeyun Shi +9 more

To distinguish the contributions of electromagnetically induced transparency (EIT) and Autler-Townes splitting (ATS) in their applications in precision laser spectroscopy, we propose a real-imaginary spectrum decomposition method to investigate the transparency spectra in a four-level microwave (MW) dressed Rydberg system. We show that the opening transparency windows in the absorption spectra of probe field is a prominent character by EIT, EIT-ATS crossover, and ATS when the MW field is turned off and the intensity of the control field is adjusted. When the MW field is turned on and gradually increased, the EIT is destroyed and disappears. In addition, the most prominent characters that open a transparency window are the EIT-ATS crossover and the ATS. Then, if we further increase the intensity of the MW field, we find that the transparency windows open mainly due to the ATS. Compared to the previous considerations of this issue, which were limited to three-level systems, our four-level scheme reported here is useful for understanding the features of quantum interference in multilevel atomic systems, and has potential applications to study enhanced sensitivity, measurement spectroscopic, quantum processing, quantum communication, and transmission.

Optics Express•May 20, 2024•0 citations
Exploring enhanced nonlinear optics based on electromagnetically induced transparency (EIT) has always been one of the striking issues in cavity quantum electrodynamics. However, it is not clear whether the validity of EIT in enhancing nonlinear processes is universal. In this paper we demonstrate an efficient frequency conversion scheme via Autler-Townes splitting, instead of the so-called EIT mechanism, in a three-level quantum system. Because the selective system can be used to implement the conventional three-level EIT phenomenon, we present a direct evidence for the breakdown of nonlinear processes assisted by EIT. This strongly suggests that previously physical insight into the application of the standard EIT technique in nonlinear optics is not sufficient enough.
We present a theoretical study of high-efficiency four-wave mixing (FWM) sum-frequency generation beyond a pure electromagnetically induced transparency (EIT) technique in a five-level atomic system. In our FWM scheme, with the assistance of two Λ-type subsystems utilized to create EIT and Autler-Townes splitting (ATS), a synergetic mechanism of EIT and ATS, or a dual-ATS mechanism is induced. These novel mechanisms can have a significant impact on the FWM process in the optically thick medium, and the FWM efficiency can be several orders of magnitude larger than that obtained from the pure EIT method. This Letter opens up a new perspective for exploring enhanced quantum nonlinear optical phenomena.
We demonstrate Autler-Townes (AT) splitting of four-wave mixing in an electromagnetically induced transparency window, which results from the destructive interference between a three-photon process and a five-photon process. The primary and secondary AT splittings are achieved via induced atomic coherence in a four-level Y-type atomic system. Theoretical calculations fit well with the experimentally measured results. Such controlled multichannel splitting of nonlinear optical signals can have potential applications in optical communication and quantum information processing.
Abstract Discerning electromagnetically induced transparency (EIT) from Autler–Townes splitting (ATS) is a significant issue in quantum optics and has attracted wide attention in various three-level configurations. Here we present a detailed study of EIT and ATS in a five-level atomic system considered to be composed of a four-level Y-type subsystem and a three-level Λ-type subsystem. In our theoretical calculations with standard density matrix formalism and steady-state approximation, we obtain the general analytical expression of the first-order matrix element responsible for the probe-field absorption. In light of the well-known three-level EIT and ATS criteria, we numerically show an intersection of EIT with ATS for the Y-type subsystem. Furthermore, we show that an EIT dip is sandwiched between two ATS dips (i.e., multi-dip mixture of EIT and ATS) in the absorption line for the five-level system, which can be explained by the dressed-state theory and Fano interference.
Electromagnetically induced transparency (EIT) and Autler-Townes (AT) splitting are two phenomena that could be featured in a variety of three-level atomic systems. The considered phenomena, EIT and AT, are similar ``looking'' in the sense that they are both characterized by a reduction in absorption of a weak field in the presence of a stronger field. In this paper, we explicitly set the threshold of separation between EIT and AT splitting in a unified study of four different three-level atomic systems. Two resonances are studied and compared in each case. A comparison of the magnitudes of the resonances reveals two coupling-field regimes and two categories of three-level system.
Abstract Electromagnetically induced transparency (EIT) plays an important role in enhancing nonlinear optical processes at the quantum level. This paper proposes an accessible scheme for realizing high‐efficiency second‐order nonlinear difference‐frequency generation beyond the conventional EIT technique in superconducting circuits. By designing two subsystems to create two transparency windows from Autler–Townes splitting (ATS), a dual‐ATS mechanism is triggered in the scheme. This mechanism leads to an efficient difference‐frequency generation, and the efficiency obtained here can be four orders of magnitude larger than that of the EIT scheme. This study may pave a way for exploring ATS‐enhanced nonlinear optics.
To distinguish the contributions of electromagnetically induced transparency (EIT) and Autler-Townes splitting (ATS) in their applications in precision laser spectroscopy, we propose a real-imaginary spectrum decomposition method to investigate the transparency spectra in a four-level microwave (MW) dressed Rydberg system. We show that the opening transparency windows in the absorption spectra of probe field is a prominent character by EIT, EIT-ATS crossover, and ATS when the MW field is turned off and the intensity of the control field is adjusted. When the MW field is turned on and gradually increased, the EIT is destroyed and disappears. In addition, the most prominent characters that open a transparency window are the EIT-ATS crossover and the ATS. Then, if we further increase the intensity of the MW field, we find that the transparency windows open mainly due to the ATS. Compared to the previous considerations of this issue, which were limited to three-level systems, our four-level scheme reported here is useful for understanding the features of quantum interference in multilevel atomic systems, and has potential applications to study enhanced sensitivity, measurement spectroscopic, quantum processing, quantum communication, and transmission.