Applied Optics

Two-step selective photoionization of rubidium by using a Ti:sapphire laser

Koji Tamura, Masaki Oba, Takashi Arisawa

Published Feb 20, 1993• 4 citations

Abstract

A pulsed Ti:sapphire laser (TSL) is applied for what is, to our knowledge, the first time to laser isotope separation. A collimated beam of a rubidium atom with a natural isotope composition ((85)Rb, 72%; (87)Rb, 28%) is excited selectively from the ground state to the 5(2)P(3/2) state by irradiation of the single-longitudinalmode TSL, and is photoionized by successive UV radiation. Ion spectra of each isotope indicate that each isotope is selectively photoionized.

DOI: 10.1364/ao.32.000987

Related papers

Selective excitation and chemical reactions in alkali metal vapor

V. O. Chaltykyan, G. G. Grigoryan, Yu. P. Malakyan

Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIEApr 11, 20030 citations

Resonance ionization of rubidium using sequential diode laser-driven transitions

Robert W. Shaw, Jack Phillip Young, J. Michael Ramsey

Jan 1, 19923 citations

Isotope-selective photoionization spectroscopy of barium

Darrell J. Armstrong, J. Cooper

Physical Review AApr 1, 199311 citations

Selective photoionization of the ytterbium atom by coherent two-photon excitation

Hyunmin Park, Jongmin Lee, Jai-Hyung Lee +1 more

Physical Review AMar 1, 199610 citations

Isotope-selective laser excitation and field ionization of thenF5/2Rydberg states in a thallium beam

Petr A. Bokhan, Nikolai V. Fateev, V A Kim +1 more

Laser PhysicsApr 16, 20131 citation

Polarization-based selective photoionization of ⁶⁷Zn

Christine M. Steenkamp, Frederick John Waso

Nov 7, 20240 citations

Applied Optics

Two-step selective photoionization of rubidium by using a Ti:sapphire laser

Koji Tamura, Masaki Oba, Takashi Arisawa

Published Feb 20, 1993• 4 citations

Publisher

Abstract

DOI: 10.1364/ao.32.000987

Related papers

Selective excitation and chemical reactions in alkali metal vapor

V. O. Chaltykyan, G. G. Grigoryan, Yu. P. Malakyan

We consider a gas of two-level atoms of two species (for example, natural Rb vapor consisting of two isotopes) in the field of laser radiation tuned close to resonance with the certain transition of a specific iostope. This radiation may turn to be rather close to a near lying transition of other isotope (within the linewidth of laser radiation), so it is necessary to take into account the possibility of excitation of other isotope in order to evaluate the enrichment degree if it is aimed at the isotope separation by means of selective excitation with subsequent chemcial reaction (in our example the rubidium hydride formation) of the excited isotope which is believed to take place at a rate much higher than that in the ground state of the atom.We consider a gas of two-level atoms of two species (for example, natural Rb vapor consisting of two isotopes) in the field of laser radiation tuned close to resonance with the certain transition of a specific iostope. This radiation may turn to be rather close to a near lying transition of other isotope (within the linewidth of laser radiation), so it is necessary to take into account the possibility of excitation of other isotope in order to evaluate the enrichment degree if it is aimed at the isotope separation by means of selective excitation with subsequent chemcial reaction (in our example the rubidium hydride formation) of the excited isotope which is believed to take place at a rate much higher than that in the ground state of the atom.

Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIEApr 11, 20030 citations

Resonance ionization of rubidium using sequential diode laser-driven transitions

Robert W. Shaw, Jack Phillip Young, J. Michael Ramsey

Diode laser excitation of rubidium atoms at the D2 line followed by (1 + 1) ionization using a pulsed dye laser was examined. Mass-resolved D2 spectra were recorded for both natural isotopes. Excitation using two sequential diode laser photons was accomplished by counterpropagating the beam from the 780 nm laser and one from a 775.8 laser; the latter excites Rb from the {sup 5}P{sub 3/2} level to the {sup 5}D{sub 5/2} level at 25704 cm{sup {minus}1}. A photon from the R6G laser then ionized the atom. Spectra resulting from scanning the second diode laser -- with the first an an off-resonance fixed frequency revealed both two-photon and sequential (1 + 1) processes.Diode laser excitation of rubidium atoms at the D2 line followed by (1 + 1) ionization using a pulsed dye laser was examined. Mass-resolved D2 spectra were recorded for both natural isotopes. Excitation using two sequential diode laser photons was accomplished by counterpropagating the beam from the 780 nm laser and one from a 775.8 laser; the latter excites Rb from the {sup 5}P{sub 3/2} level to the {sup 5}D{sub 5/2} level at 25704 cm{sup {minus}1}. A photon from the R6G laser then ionized the atom. Spectra resulting from scanning the second diode laser -- with the first an an off-resonance fixed frequency revealed both two-photon and sequential (1 + 1) processes.

Jan 1, 19923 citations

Isotope-selective photoionization spectroscopy of barium

Darrell J. Armstrong, J. Cooper

We demonstrate an experimental technique that selects the nuclear spin I=0 isotope $^{138}\mathrm{Ba}$ for spectroscopic measurements from a beam of natural barium containing seven stable isotopes. A cw dye laser is used to optically pump the I=3/2 isotopes $^{135}\mathrm{Ba}$ and $^{137}\mathrm{Ba}$ into the metastable 6s5d $^{1}$ ${\mathit{D}}_{2}$ and $^{3}$ ${\mathit{D}}_{1,2}$ levels via the 6s6p $^{1}$ ${\mathit{P}}_{1}$ excited state, leaving nearly pure $^{138}\mathrm{Ba}$ in the ground state. Photoionization spectra of the excited 5d6p $^{3}$ ${\mathit{D}}_{1}$ even isotope state recorded with optical pumping of $^{135}\mathrm{Ba}$ and $^{137}\mathrm{Ba}$ to the metastable levels are essentially devoid of forbidden features associated with the hyperfine interaction in the odd isotopes.We demonstrate an experimental technique that selects the nuclear spin I=0 isotope $^{138}\mathrm{Ba}$ for spectroscopic measurements from a beam of natural barium containing seven stable isotopes. A cw dye laser is used to optically pump the I=3/2 isotopes $^{135}\mathrm{Ba}$ and $^{137}\mathrm{Ba}$ into the metastable 6s5d $^{1}$${\mathit{D}}_{2}$ and $^{3}$${\mathit{D}}_{1,2}$ levels via the 6s6p $^{1}$${\mathit{P}}_{1}$ excited state, leaving nearly pure $^{138}\mathrm{Ba}$ in the ground state. Photoionization spectra of the excited 5d6p $^{3}$${\mathit{D}}_{1}$ even isotope state recorded with optical pumping of $^{135}\mathrm{Ba}$ and $^{137}\mathrm{Ba}$ to the metastable levels are essentially devoid of forbidden features associated with the hyperfine interaction in the odd isotopes.

Physical Review AApr 1, 199311 citations

Selective photoionization of the ytterbium atom by coherent two-photon excitation

Hyunmin Park, Jongmin Lee, Jai-Hyung Lee +1 more

Highly selective photoionization of the ytterbium atom by coherent two-photon excitation was demonstrated experimentally. The Yb atom was excited by two single-mode lasers and ionized by a time-delayed broadband laser. The isotope ratio of the ions was analyzed by a time-of-flight mass spectrometer. The ion yield and the selectivity were recorded as a function of detuning of the first exciting laser. The maximum of ion yield was observed when the laser was detuned from resonance. The selectivity of $^{168}\mathrm{Yb}$ was increased higher than 20 000 when the laser was blue-detuned to the most efficient position. Also, numerical analysis was performed to explain the experimental results. \textcopyright{} 1996 The American Physical Society.Highly selective photoionization of the ytterbium atom by coherent two-photon excitation was demonstrated experimentally. The Yb atom was excited by two single-mode lasers and ionized by a time-delayed broadband laser. The isotope ratio of the ions was analyzed by a time-of-flight mass spectrometer. The ion yield and the selectivity were recorded as a function of detuning of the first exciting laser. The maximum of ion yield was observed when the laser was detuned from resonance. The selectivity of $^{168}\mathrm{Yb}$ was increased higher than 20 000 when the laser was blue-detuned to the most efficient position. Also, numerical analysis was performed to explain the experimental results. \textcopyright{} 1996 The American Physical Society.

Physical Review AMar 1, 199610 citations

Isotope-selective laser excitation and field ionization of thenF5/2Rydberg states in a thallium beam

Petr A. Bokhan, Nikolai V. Fateev, V A Kim +1 more

The effective isotope-selective excitation and field ionization of the 16F5/2 thallium Rydberg states have been studied experimentally. The 16F5/2 states were excited by the two-step scheme 6P1/2→6D3/2→nF5/2 in a dense collimated atomic beam by means of monochromatic radiation from two frequency tunable lasers (λ1 = 276.9 nm, λ2 = 773–808 nm) with a mean power density of more than 1 W.The largest selectivity of excitation in this scheme takes place in the first step 6P1/2→6D3/2. The experiments showed that the main reason for the limiting selectivity excitation of the Rydberg states is the field broadening of the absorption resonances at the first and second steps of the excitation scheme. The excitation efficiency of this scheme is considerably governed by the parameters of the laser radiation at the second step and an electric field pulse.The effective isotope-selective excitation and field ionization of the 16F5/2 thallium Rydberg states have been studied experimentally. The 16F5/2 states were excited by the two-step scheme 6P1/2→6D3/2→nF5/2 in a dense collimated atomic beam by means of monochromatic radiation from two frequency tunable lasers (λ1 = 276.9 nm, λ2 = 773–808 nm) with a mean power density of more than 1 W.The largest selectivity of excitation in this scheme takes place in the first step 6P1/2→6D3/2. The experiments showed that the main reason for the limiting selectivity excitation of the Rydberg states is the field broadening of the absorption resonances at the first and second steps of the excitation scheme. The excitation efficiency of this scheme is considerably governed by the parameters of the laser radiation at the second step and an electric field pulse.

Laser PhysicsApr 16, 20131 citation

Polarization-based selective photoionization of ⁶⁷Zn

Christine M. Steenkamp, Frederick John Waso

Isotope selective photoionization of ⁶⁷Zn is demonstrated with broadband excitation light (∼ 3.4 GHz), temporally separated laser pulses in the presence of a weak external magnetic field. Starting with natural zinc metal (∼ 4% ⁶⁷Zn) the ion sample was enriched to ∼ 90% ⁶⁷Zn. Efficient suppression of the ionization of the even-mass isotopes was achieved by intermediate state alignment in the excitation scheme 4𝑠2 ¹𝑆₀ → 4𝑠4𝑝 ³𝑃₁ → 4𝑠4𝑑 ³𝐷₁, followed by nonresonant photoionization. The first excitation pulse was linearly polarized parallel to the transverse component of the external magnetic field and the linear polarization of the second excitation pulse was rotated to compensate for Larmor precession of the quantization axis during the temporal delay between the two excitations. This is the first systematic study, in the context of resonance ionization, investigating the independent and continuous rotation of the polarizations of the excitation pulses and demonstrating efficient compensation for the presence of an external magnetic field that has an arbitrary direction. Experimental results are supported by a vector model combined with rate equations.Isotope selective photoionization of ⁶⁷Zn is demonstrated with broadband excitation light (∼ 3.4 GHz), temporally separated laser pulses in the presence of a weak external magnetic field. Starting with natural zinc metal (∼ 4% ⁶⁷Zn) the ion sample was enriched to ∼ 90% ⁶⁷Zn. Efficient suppression of the ionization of the even-mass isotopes was achieved by intermediate state alignment in the excitation scheme 4𝑠2 ¹𝑆₀ → 4𝑠4𝑝 ³𝑃₁ → 4𝑠4𝑑 ³𝐷₁, followed by nonresonant photoionization. The first excitation pulse was linearly polarized parallel to the transverse component of the external magnetic field and the linear polarization of the second excitation pulse was rotated to compensate for Larmor precession of the quantization axis during the temporal delay between the two excitations. This is the first systematic study, in the context of resonance ionization, investigating the independent and continuous rotation of the polarizations of the excitation pulses and demonstrating efficient compensation for the presence of an external magnetic field that has an arbitrary direction. Experimental results are supported by a vector model combined with rate equations.

Nov 7, 20240 citations

We demonstrate an experimental technique that selects the nuclear spin I=0 isotope

^{138}\mathrm{Ba}

for spectroscopic measurements from a beam of natural barium containing seven stable isotopes. A cw dye laser is used to optically pump the I=3/2 isotopes

^{135}\mathrm{Ba}

and

^{137}\mathrm{Ba}

into the metastable 6s5d

^{1}

{\mathit{D}}_{2}

and

^{3}

{\mathit{D}}_{1,2}

levels via the 6s6p

^{1}

{\mathit{P}}_{1}

excited state, leaving nearly pure

^{138}\mathrm{Ba}

in the ground state. Photoionization spectra of the excited 5d6p

^{3}

{\mathit{D}}_{1}

even isotope state recorded with optical pumping of

^{135}\mathrm{Ba}

and

^{137}\mathrm{Ba}

to the metastable levels are essentially devoid of forbidden features associated with the hyperfine interaction in the odd isotopes.

^{168}\mathrm{Yb}

was increased higher than 20 000 when the laser was blue-detuned to the most efficient position. Also, numerical analysis was performed to explain the experimental results. \textcopyright{} 1996 The American Physical Society.