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

Applied Physics Letters

Two color pumping of the Rb D2 line laser (780 nm) through the photoassociation of Rb-Ar or Rb-Xe thermal pairs: Realization of a quantum efficiency above one

Andrey E. Mironov, William Goldshlag, James Gary Eden

Published Jul 27, 2015• 14 citations
Publisher

Abstract

A two color process for optical pumping of the Rb D2 line laser (λ = 780 nm) in Rb vapor-rare gas mixtures is demonstrated to yield an overall quantum efficiency > 1. Combining photoexcitation of the Rb D2 line blue satellite in Rb-Xe or Rb-Ar mixtures with free ← free optical pumping of the A2Π12←X2Σ12+ transition at large internuclear separation (R > 5 Å) also increases the laser efficiency and pump absorption coefficient, relative to the single color, B ← X pumped system, by a factor of 1.7 and more than an order of magnitude, respectively. Simultaneous photopumping of Rb-Xe thermal collision pairs at 760 nm (D2 satellite) and 794.3 nm results in a 780 nm (D2 line) laser with a quantum efficiency of 1.008 which corresponds to the removal of ∼102 cm–1 (12.6 meV) of thermal energy per emitted photon.

DOI
10.1063/1.4927536

Related papers

Lasing on the D lines of sodium pumped by free→free transitions of Na-Xe collision pairs

J. Darby Hewitt, James Gary Eden

Lasing on the D1 and D2 lines of Na (589.6 and 589.0 nm, respectively) has been generated simultaneously by photoexciting free→free transitions of thermal Na-Xe collision pairs. Pumping the blue satellite of the Na D2 line in Na/Xe mixtures (λ ≈ 560 nm) selectively interacts with Na-Xe pairs having an instantaneous internuclear separation of ∼5 Å and culminates in the population of both Na (32PJ) fine structure levels. The spectral width of the laser excitation spectrum is 1.3 nm (centered at 560.1 nm) and the 32P3/2→32S1/2 (D2) laser linewidth was measured to be 9.2 ± 0.6 GHz, which is consistent with a coefficient of 18.4 MHz/Torr for broadening of the D2 589.0 nm transition by Xe.

Applied Physics Letters•Dec 10, 2012•7 citations

Pumping of atomic alkali lasers by photoexcitation of a resonance line blue satellite and alkali-rare gas excimer dissociation

Jason D. Readle, C. J. Wagner, J. T. Verdeyen +3 more

Photoassociation of alkali-rare gas atomic collision pairs provides an alternative approach to optically pumping atomic alkali lasers. Lasing on the 6 P21/2→6 S21/2 (D1) transition of Cs has been observed when the blue satellite of the 6 P23/2←6 S21/2 (D2) transition, peaking at ∼837 nm for mixtures of Cs vapor, Ar, and ethane, is pumped by a pulsed dye laser. For 50% output coupling, laser threshold with respect to absorbed pump energy is ∼40 μJ at T=435 K and the slope efficiency approaches 10%. The measured spectral breadth for the blue satellite (≳5 nm at 410 K) will accommodate cw pumping of the Cs laser with conventional semiconductor lasers.

Applied Physics Letters•Jun 22, 2009•42 citations

Two Color Laser Pumping of Alkali-Noble Gas Atomic Lasers

Andrey E. Mironov, J. Gary Eden

Two color optical pumping of the Rb D2-laser(780nm) through the RbXe excimer has been realized. By simultaneously photoexciting the D2-blue(760nm) and the red satellite of the D1 transition, lasing efficiency is more than doubled.

Frontiers in Optics•Jan 1, 2014•0 citations

Optically Pumped Atomic Rubidium Lasers: Two-Photon and Exciplex Excitation Mechanisms

Jeffrey Gallagher

Abstract : The Doppler-broadened two-photon absorption (TPA) cross-section for the 52S1/2- 52D5/2 transition in Rb is measured using direct absorption methods. A detailed model of the intensity profile was developed to account for a focused Gaussian beam propagating through a two-photon absorption medium. A peak absorbance of 24% was observed for an intensity of 6.28 kW/cm2 at the focus, a Rb density of 4.6 x 1015 cm-3 concentrations from 1.61-8.52 x 10(15) cm-3 line. Extracting the hyperfine-broadened TPA cross-section from 87 test configurations, while varying the pump power, alkali concentration and focal length, yielded an error weighted average of 6.75x10-21 cm4/W. This cross-section is sufficient for a pulsed dye laser to bleach the pump transition in the Two-Photon Pumped Alkali Laser (TPAL) that lases at 420 nm and 5.2 mum. Additionally, optically pumped atomic rubidium lasers pumped in the blue satellite of the D2 line from the ground Rb-Ar or Rb-Kr collision pair to the dissociative B2 sum 1/2 produce laser emission at 780.2 nm. Lasing is achieved for the Rb-Ar system and 757.1 - 760.4 nm for the Rb-Kr system. Slope efficiencies exceed 0.25% using a heat pipe configuration. The gain is very high with photon build-up times of 1-3.7 ns.

•Jun 1, 2013•2 citations

Cs 8943 nm laser pumped by photoassociation of Cs-Kr pairs: excitation of the Cs D_2 blue and red satellites

Jason D. Readle, J. T. Verdeyen, James Gary Eden +4 more

Lasing on the D(1) transition (6P1/22-->6S1/22) of Cs has been observed by photoassociating Cs-Kr atomic pairs with a tunable, pulsed dye laser. Pumping of the blue or red satellites of the Cs D(2) line (62P3/2<==>62S1/2), peaking at approximately 841.1 nm and approximately 853 nm (respectively) in Cs/Kr/C(2)H(6) gas mixtures, provides a photodissociation laser in which the CsKr excimer parent molecule is not, at any point in the pumping process, in a bound electronic state. Relative to the absorbed pump pulse energy, laser slope efficiencies greater than or approximately 5% have been measured when the Cs number density is in the range of 5x10(14)-1.5x10(15) cm(-3) and the pump wavelength is 841.1 nm. Direct photoexcitation of the Cs 6P3/22 state at 852.1 nm under these conditions is a less efficient pathway for pumping the 894.3 nm laser, presumably as a result of competing nonlinear optical processes such as 1+2 resonantly enhanced multiphoton ionization of the alkali atom.

Optics Letters•Nov 18, 2009•38 citations

Four level, atomic Cs laser at 852.1 nm with a quantum efficiency above 98%: Observation of three body photoassociation

Jason D. Readle, James Gary Eden, J. T. Verdeyen +1 more

Lasing on the D2 (6p P23/2→6s S21/2) transition of atomic Cs at 852.1 nm has been observed with a four level system in which the Cs 6p P23/2 state is pumped by the photoassociation and subsequent dissociation of Cs-rare gas collision pairs. Characterized by a quantum efficiency >98%, this laser requires no atomic precursor to the upper laser level and provides oscillation on an alkali transition inaccessible to three level, photopumped alkali laser systems. Measurements of photoabsorption and pump energy threshold in Cs–Ar–Kr mixtures reveal the influence of three body photoassociation.

Applied Physics Letters•Jul 12, 2010•33 citations
A two color process for optical pumping of the Rb D2 line laser (λ = 780 nm) in Rb vapor-rare gas mixtures is demonstrated to yield an overall quantum efficiency > 1. Combining photoexcitation of the Rb D2 line blue satellite in Rb-Xe or Rb-Ar mixtures with free ← free optical pumping of the A2Π12←X2Σ12+ transition at large internuclear separation (R > 5 Å) also increases the laser efficiency and pump absorption coefficient, relative to the single color, B ← X pumped system, by a factor of 1.7 and more than an order of magnitude, respectively. Simultaneous photopumping of Rb-Xe thermal collision pairs at 760 nm (D2 satellite) and 794.3 nm results in a 780 nm (D2 line) laser with a quantum efficiency of 1.008 which corresponds to the removal of ∼102 cm–1 (12.6 meV) of thermal energy per emitted photon.
Lasing on the D1 and D2 lines of Na (589.6 and 589.0 nm, respectively) has been generated simultaneously by photoexciting free→free transitions of thermal Na-Xe collision pairs. Pumping the blue satellite of the Na D2 line in Na/Xe mixtures (λ ≈ 560 nm) selectively interacts with Na-Xe pairs having an instantaneous internuclear separation of ∼5 Å and culminates in the population of both Na (32PJ) fine structure levels. The spectral width of the laser excitation spectrum is 1.3 nm (centered at 560.1 nm) and the 32P3/2→32S1/2 (D2) laser linewidth was measured to be 9.2 ± 0.6 GHz, which is consistent with a coefficient of 18.4 MHz/Torr for broadening of the D2 589.0 nm transition by Xe.
Photoassociation of alkali-rare gas atomic collision pairs provides an alternative approach to optically pumping atomic alkali lasers. Lasing on the 6 P21/2→6 S21/2 (D1) transition of Cs has been observed when the blue satellite of the 6 P23/2←6 S21/2 (D2) transition, peaking at ∼837 nm for mixtures of Cs vapor, Ar, and ethane, is pumped by a pulsed dye laser. For 50% output coupling, laser threshold with respect to absorbed pump energy is ∼40 μJ at T=435 K and the slope efficiency approaches 10%. The measured spectral breadth for the blue satellite (≳5 nm at 410 K) will accommodate cw pumping of the Cs laser with conventional semiconductor lasers.
Abstract : The Doppler-broadened two-photon absorption (TPA) cross-section for the 52S1/2- 52D5/2 transition in Rb is measured using direct absorption methods. A detailed model of the intensity profile was developed to account for a focused Gaussian beam propagating through a two-photon absorption medium. A peak absorbance of 24% was observed for an intensity of 6.28 kW/cm2 at the focus, a Rb density of 4.6 x 1015 cm-3 concentrations from 1.61-8.52 x 10(15) cm-3 line. Extracting the hyperfine-broadened TPA cross-section from 87 test configurations, while varying the pump power, alkali concentration and focal length, yielded an error weighted average of 6.75x10-21 cm4/W. This cross-section is sufficient for a pulsed dye laser to bleach the pump transition in the Two-Photon Pumped Alkali Laser (TPAL) that lases at 420 nm and 5.2 mum. Additionally, optically pumped atomic rubidium lasers pumped in the blue satellite of the D2 line from the ground Rb-Ar or Rb-Kr collision pair to the dissociative B2 sum 1/2 produce laser emission at 780.2 nm. Lasing is achieved for the Rb-Ar system and 757.1 - 760.4 nm for the Rb-Kr system. Slope efficiencies exceed 0.25% using a heat pipe configuration. The gain is very high with photon build-up times of 1-3.7 ns.
Lasing on the D(1) transition (6P1/22-->6S1/22) of Cs has been observed by photoassociating Cs-Kr atomic pairs with a tunable, pulsed dye laser. Pumping of the blue or red satellites of the Cs D(2) line (62P3/2<==>62S1/2), peaking at approximately 841.1 nm and approximately 853 nm (respectively) in Cs/Kr/C(2)H(6) gas mixtures, provides a photodissociation laser in which the CsKr excimer parent molecule is not, at any point in the pumping process, in a bound electronic state. Relative to the absorbed pump pulse energy, laser slope efficiencies greater than or approximately 5% have been measured when the Cs number density is in the range of 5x10(14)-1.5x10(15) cm(-3) and the pump wavelength is 841.1 nm. Direct photoexcitation of the Cs 6P3/22 state at 852.1 nm under these conditions is a less efficient pathway for pumping the 894.3 nm laser, presumably as a result of competing nonlinear optical processes such as 1+2 resonantly enhanced multiphoton ionization of the alkali atom.
Lasing on the D2 (6p P23/2→6s S21/2) transition of atomic Cs at 852.1 nm has been observed with a four level system in which the Cs 6p P23/2 state is pumped by the photoassociation and subsequent dissociation of Cs-rare gas collision pairs. Characterized by a quantum efficiency >98%, this laser requires no atomic precursor to the upper laser level and provides oscillation on an alkali transition inaccessible to three level, photopumped alkali laser systems. Measurements of photoabsorption and pump energy threshold in Cs–Ar–Kr mixtures reveal the influence of three body photoassociation.