Session Index

Quantum Electronics

Quantum Electronics IV
Saturday, Dec. 5, 2015  13:10-14:40
Chair: Cheng-Maw Cheng (鄭澄懋)
Room: Delta B06
13:10 - 13:40 Paper No.  2015-SAT-S0304-O001
Yu-Miin Sheu Using ultrafast nonlinear optics to understand magnetoelectric multiferroics of spiral-spin origin

Multiferroic manganites possess ferroelectric order of spiral-spin origin. The two spin states, ab- and bc-spiral, result in the ferroelectric order along the crystal a or c axis respectively. Using time-resolved second harmonic generation to probe broken inversion symmetry along a-axis originating from ab-spiral-spin state, I observed a threshold of photoexcitation, at which typical and novel spin-relaxation is discriminated through a drastic change in dynamic. In low excitation region, the dynamics behave similarly to general manganites, but no critical slowing down occurs when system is approaching the transition of first order between the ab- and bc-spiral-spin state. However, an exotic long-lived state is revealed and proven to depend strongly on the magnetic field and temperature. We propose that this induced long-lived state is a metastable bc-spiral-spin state, created from the ab-spiral ground state.

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13:40 - 13:55 Paper No.  2015-SAT-S0304-O002
Wen-Zheng Xu Novel Quantum Dot Surface Emission DFB Lasers with ITO Claddings

We successfully demonstrated a novel electrically driven surface emitting InAs quantum dot (QD) distributed feedback (DFB) laser with an ITO cladding layer. The laser characteristics were measured and analyzed. The lasing wavelength located at about 1.3 m. In addition, the low threshold current density of 210 A/cm2 was observed.

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13:55 - 14:10 Paper No.  2015-SAT-S0304-O003
Jhao-Hang He Numerical Analysis of Zn-Diffusion Oxide-Confined Vertical-Cavity Surface-Emitting Lasers

The effect of Zn-diffusion aperture is numerically analyzed in oxide-confined vertical-cavity surface-emitting lasers (VCSELs). The simulation results demonstrate that high order modes is suppressed by Zn-diffusion due to high free carrier absorption and reduced reflectivity, but with degraded modulation frequency response.

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14:10 - 14:25 Paper No.  2015-SAT-S0304-O004
Chien-Lin Chen Investigation of noise like pulse from net normal Yb-doped fiber laser based on nonlinear polarization rotation mechanism

We investigated the noise-like pulse from a passive mode-locked Yb-doped fiber laser within net normal dispersion region which reveals the characteristic of broad spectrum bandwidth and double scale autocorrelation trace. With the external cavity grating pairs, the pulsewidth of noise like pulse has been compressed to be about 11.6 ps.

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14:25 - 14:40 Paper No.  2015-SAT-S0304-O005
Po-Yen Lai Numerical Study of Extreme Ultraviolet Light Emission in Laser-produced Plasmas

A numerical model based on hydrodynamic approaches with consideration of plasma dynamics, ionization processes and induced atomic radiation has been developed to study extreme ultraviolet (EUV) light emission in laser-produced plasmas (LPP). Based on simulation results, the dependency of EUV emission and opacity on plasma parameters are discussed.

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