Frequency-domain optical hole burning of the ${\mathit{R}}_{1}$ line ${[}^{4}$ ${\mathit{A}}_{2}$ (-1/2)\ensuremath{\leftrightarrows}E\ifmmode\bar\else\textasciimacron\fi{}(-1/2) transition] in dilute ruby is studied at 2 K and with a field of 3.6 kG applied along the c axis. A pump-probe (PP) technique is used with precise probe-frequency shifting obtained by an acousto-optic modulator. For sufficiently short PP pulses (50 \ensuremath{\mu}s), two holes (narrow and wide) are observed. The narrow (\ensuremath{\sim}20 kHz half width at half maximum at low power) hole-width dependence on Rabi frequency approximately agrees with that inferred from free-induction-decay measurements. For the present concentration (0.0034 wt. % ${\mathrm{Cr}}_{2}$ ${\mathrm{O}}_{3}$ ) and field, the narrow hole width is determined by fluctuating fields produced by Cr-Cr spin flips [A. Szabo, T. Muramoto, and R. Kaarli, Phys. Rev. B 42, 7769 (1990)]. When the PP delay time is varied, the amplitude of the narrow hole decays with a 1/e time constant of \ensuremath{\sim}300 \ensuremath{\mu}s compared to the E\ifmmode\bar\else\textasciimacron\fi{} fluorescence lifetime of 4 ms. The wide hole (\ensuremath{\sim}500 kHz half width at half maximum) is due to Al-Cr superhyperfine interactions and is created by a spectral diffusion mechanism driven by Al-spin flipping in the host lattice.Frequency-domain optical hole burning of the ${\mathit{R}}_{1}$ line ${[}^{4}$${\mathit{A}}_{2}$(-1/2)\ensuremath{\leftrightarrows}E\ifmmode\bar\else\textasciimacron\fi{}(-1/2) transition] in dilute ruby is studied at 2 K and with a field of 3.6 kG applied along the c axis. A pump-probe (PP) technique is used with precise probe-frequency shifting obtained by an acousto-optic modulator. For sufficiently short PP pulses (50 \ensuremath{\mu}s), two holes (narrow and wide) are observed. The narrow (\ensuremath{\sim}20 kHz half width at half maximum at low power) hole-width dependence on Rabi frequency approximately agrees with that inferred from free-induction-decay measurements. For the present concentration (0.0034 wt. % ${\mathrm{Cr}}_{2}$${\mathrm{O}}_{3}$) and field, the narrow hole width is determined by fluctuating fields produced by Cr-Cr spin flips [A. Szabo, T. Muramoto, and R. Kaarli, Phys. Rev. B 42, 7769 (1990)]. When the PP delay time is varied, the amplitude of the narrow hole decays with a 1/e time constant of \ensuremath{\sim}300 \ensuremath{\mu}s compared to the E\ifmmode\bar\else\textasciimacron\fi{} fluorescence lifetime of 4 ms. The wide hole (\ensuremath{\sim}500 kHz half width at half maximum) is due to Al-Cr superhyperfine interactions and is created by a spectral diffusion mechanism driven by Al-spin flipping in the host lattice.

Physical review. B, Condensed matterDec 1, 199148 citations

Effects of an electric field on the laser emission of ruby

W. Kaiser, H.E. Lessing

The European Physical Journal ADec 1, 19634 citations

Transient hole-burning and free induction decay as a probe of multi-timescale host spin dynamics in low-temperature ion-doped crystals

Pavel A Apanasevich, S. Ya. Kilin, Alexander P. Nizovtsev +1 more

Transient hole-burning and free induction decay (FID) in low-temperature ion-doped crystals are studied consistently using the model of two jump processes Ut equals Ut1 + Ut2 characterized by essentially different jump rates v1 >> v2 and distribution widths (sigma) 1 << (sigma) 2 for the impurity ion optical transition frequency fluctuations Ut due to the bulk and the frozen core spin flipping. At short pump/probe pulsewidth T and short delay time (tau) d ((tau) d, T << v2-1) the calculated hole shape is narrow with the hole width determined by Ut1 process characteristics only. The hole width in this case coincides with the calculated FID rate. At long delay (tau) d >= v2-1 the hole becomes a wide lorentzian with the halfwidth 2(sigma) 2. The theory fits well the experimental data by A. Szabo et. al. on narrow hole burning and FID in ruby under low and high magnetic fields supposing the fluctuations Ut1 to be rather slow ((sigma) 21/v21 equals 0.5).Transient hole-burning and free induction decay (FID) in low-temperature ion-doped crystals are studied consistently using the model of two jump processes Ut equals Ut1 + Ut2 characterized by essentially different jump rates v1 >> v2 and distribution widths (sigma) 1 << (sigma) 2 for the impurity ion optical transition frequency fluctuations Ut due to the bulk and the frozen core spin flipping. At short pump/probe pulsewidth T and short delay time (tau) d ((tau) d, T << v2-1) the calculated hole shape is narrow with the hole width determined by Ut1 process characteristics only. The hole width in this case coincides with the calculated FID rate. At long delay (tau) d >= v2-1 the hole becomes a wide lorentzian with the halfwidth 2(sigma) 2. The theory fits well the experimental data by A. Szabo et. al. on narrow hole burning and FID in ruby under low and high magnetic fields supposing the fluctuations Ut1 to be rather slow ((sigma) 21/v21 equals 0.5).

Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIEMay 10, 19960 citations

Splitting of the Emission Lines of Ruby by an External Electric Field

W. Kaiser, Satoru Sugano, Darwin L. Wood

Physical Review LettersJun 1, 196182 citations

Experimental Tests of the Optical Bloch Equations for Solids

Alex Szabo

Following a brief review of laser frequency and time domain techniques for overcoming inhomogeneous broadening of optical transitions in solids, recent studies on the failure of the optical Bloch equations (OBE) in describing saturation and coherent transient phenomena in ruby will be discussed. Experiments using free induction decay (FID), as in the original work on the system Pr3+:LaF3 by DeVoe and Brewer1, as well as extensions to rotary echos2 and hole-burning3 will be described. At low fields (~ 0.4 T), the time and frequency domain linewidth variation with Rabi frequency agree provided care is taken to avoid line broadening caused by spectral diffusion4. Recent work at high fields (~ 5 T), where Cr-Cr electron spin flipping is suppressed5, shows that spectral diffusion decreases and the dephasing time increases. Observed frequency domain hole widths as narrow as 18 kHz (FWHM) have been obtained for the 4 A2(−1/2)→E¯(−1/2) optical transition in dilute ruby using a pump-probe technique4. Work with such narrow holes emphasizes the fundamental limits imposed by the uncertainty principle and as an aside, a thought experiment where single photons are transmitted through "frequency slits" will be discussed.Following a brief review of laser frequency and time domain techniques for overcoming inhomogeneous broadening of optical transitions in solids, recent studies on the failure of the optical Bloch equations (OBE) in describing saturation and coherent transient phenomena in ruby will be discussed. Experiments using free induction decay (FID), as in the original work on the system Pr3+:LaF3 by DeVoe and Brewer1, as well as extensions to rotary echos2 and hole-burning3 will be described. At low fields (~ 0.4 T), the time and frequency domain linewidth variation with Rabi frequency agree provided care is taken to avoid line broadening caused by spectral diffusion4. Recent work at high fields (~ 5 T), where Cr-Cr electron spin flipping is suppressed5, shows that spectral diffusion decreases and the dephasing time increases. Observed frequency domain hole widths as narrow as 18 kHz (FWHM) have been obtained for the 4 A2(−1/2)→E¯(−1/2) optical transition in dilute ruby using a pump-probe technique4. Work with such narrow holes emphasizes the fundamental limits imposed by the uncertainty principle and as an aside, a thought experiment where single photons are transmitted through "frequency slits" will be discussed.

Spectral Hole-Burning and Related Spectroscopies: Science and ApplicationsJan 1, 19920 citations

Narrow optical hole burning and related effects in ruby

T. Endo, T. Muramoto, T. Hashi

Optics CommunicationsMar 1, 19839 citations

Frequency-domain optical hole burning of the

{\mathit{R}}_{1}

line

{[}^{4}

{\mathit{A}}_{2}

(-1/2)\ensuremath{\leftrightarrows}E\ifmmode\bar\else\textasciimacron\fi{}(-1/2) transition] in dilute ruby is studied at 2 K and with a field of 3.6 kG applied along the c axis. A pump-probe (PP) technique is used with precise probe-frequency shifting obtained by an acousto-optic modulator. For sufficiently short PP pulses (50 \ensuremath{\mu}s), two holes (narrow and wide) are observed. The narrow (\ensuremath{\sim}20 kHz half width at half maximum at low power) hole-width dependence on Rabi frequency approximately agrees with that inferred from free-induction-decay measurements. For the present concentration (0.0034 wt. %

{\mathrm{Cr}}_{2}

{\mathrm{O}}_{3}

) and field, the narrow hole width is determined by fluctuating fields produced by Cr-Cr spin flips [A. Szabo, T. Muramoto, and R. Kaarli, Phys. Rev. B 42, 7769 (1990)]. When the PP delay time is varied, the amplitude of the narrow hole decays with a 1/e time constant of \ensuremath{\sim}300 \ensuremath{\mu}s compared to the E\ifmmode\bar\else\textasciimacron\fi{} fluorescence lifetime of 4 ms. The wide hole (\ensuremath{\sim}500 kHz half width at half maximum) is due to Al-Cr superhyperfine interactions and is created by a spectral diffusion mechanism driven by Al-spin flipping in the host lattice.