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   <dim:field mdschema="dc" element="contributor" qualifier="advisor" lang="en_US">Erich P. Ippen.</dim:field>
   <dim:field mdschema="dc" element="contributor" qualifier="author" lang="en_US">Ripin, Daniel Jacob, 1973-</dim:field>
   <dim:field mdschema="dc" element="contributor" qualifier="other" lang="en_US">Massachusetts Institute of Technology. Dept. of Physics.</dim:field>
   <dim:field mdschema="dc" element="contributor" qualifier="department">Massachusetts Institute of Technology. Department of Physics</dim:field>
   <dim:field mdschema="dc" element="date" qualifier="accessioned">2005-08-23T18:56:01Z</dim:field>
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   <dim:field mdschema="dc" element="date" qualifier="copyright" lang="en_US">2002</dim:field>
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   <dim:field mdschema="dc" element="identifier" qualifier="oclc" lang="en_US">50421132</dim:field>
   <dim:field mdschema="dc" element="description" lang="en_US">Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Physics, 2002.</dim:field>
   <dim:field mdschema="dc" element="description" lang="en_US">Includes bibliographical references (p. 261-279).</dim:field>
   <dim:field mdschema="dc" element="description" qualifier="abstract" lang="en_US">A prismless Cr4+:YAG laser was used to generate 20 fs pulses at 1450 nm with a bandwidth of 190 nm FWHM. Intracavity group velocity dispersion was compensated with double-chirped mirrors. Pulse spectrum was observable from 1140 to >1700 nm. Broadband saturable Bragg reflectors were designed and used to ensure self-starting of 35 fs pulses in the ultrafast Cr4+:YAG laser or to generate picosecond pulses tunable from 1400 to 1525 nm. The mirrors were a 7-pair GaAs/AlxOy quarter-wave dielectric stack, and the absorber consisted of a InGaAs quantum well centered in a half-wave InP layer. Transmission was measured through a photonic bandgap crystal microcavity resonant near 1550 nm. Cavity quality factors as high as 360 were observed for cavities with a modal volume of only 2([lambda]/2n)3. Photonic crystals were used to enhance the total emission of a light emitting diode at 980 nm by 8-fold. At particular wavelengths, collected photoluminescence enhancements larger than 100 were observed.</dim:field>
   <dim:field mdschema="dc" element="description" qualifier="statementofresponsibility" lang="en_US">by Daniel Jacob Ripin.</dim:field>
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   <dim:field mdschema="dc" element="publisher" lang="en_US">Massachusetts Institute of Technology</dim:field>
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   <dim:field mdschema="dc" element="rights" qualifier="uri">http://dspace.mit.edu/handle/1721.1/7582</dim:field>
   <dim:field mdschema="dc" element="subject" lang="en_US">Physics.</dim:field>
   <dim:field mdschema="dc" element="title" lang="en_US">A few-cycle Cr⁴⁺:YAG laser and optical studies of photonic crystals</dim:field>
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   	&lt;Title>A few-cycle Cr⁴⁺:YAG laser and optical studies of photonic crystals&lt;/Title>
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   	&lt;PublicationDate>2002&lt;/PublicationDate>
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   	&lt;Abstract>A prismless Cr4+:YAG laser was used to generate 20 fs pulses at 1450 nm with a bandwidth of 190 nm FWHM. Intracavity group velocity dispersion was compensated with double-chirped mirrors. Pulse spectrum was observable from 1140 to &amp;gt;1700 nm. Broadband saturable Bragg reflectors were designed and used to ensure self-starting of 35 fs pulses in the ultrafast Cr4+:YAG laser or to generate picosecond pulses tunable from 1400 to 1525 nm. The mirrors were a 7-pair GaAs/AlxOy quarter-wave dielectric stack, and the absorber consisted of a InGaAs quantum well centered in a half-wave InP layer. Transmission was measured through a photonic bandgap crystal microcavity resonant near 1550 nm. Cavity quality factors as high as 360 were observed for cavities with a modal volume of only 2([lambda]/2n)3. Photonic crystals were used to enhance the total emission of a light emitting diode at 980 nm by 8-fold. At particular wavelengths, collected photoluminescence enhancements larger than 100 were observed.&lt;/Abstract>
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