Pub Date : 2012-11-07DOI: 10.1364/ACPC.2012.AF4A.3
J. Liu, S. Ateş, S. Stobbe, M. Lorke, P. Lodahl
Photonic crystal nanolasers have attracted great interest both for fundamental research and applications in the past decade. In photonic crystal cavities, the leakage to optical modes is strongly reduced, which increases the spontaneous emission coupling factor, β. This is a crucial parameter for the threshold characteristics of lasers. With increasing β, the well-known step-like threshold behavior becomes smoother. Although the smooth lasing transitions of photonic crystal nanolasers were observed and fitted by traditional rate equation models [1], a systematic comparison between experiments and more advanced semiconductor models of photonic crystal nanolasers is still missing [2]. The goal of this work is to get a deep understanding of the quantum dots based nanocavity lasers by comparing experiments to theory.
{"title":"Few-quantum-dot lasing in photonic crystal nanocavities","authors":"J. Liu, S. Ateş, S. Stobbe, M. Lorke, P. Lodahl","doi":"10.1364/ACPC.2012.AF4A.3","DOIUrl":"https://doi.org/10.1364/ACPC.2012.AF4A.3","url":null,"abstract":"Photonic crystal nanolasers have attracted great interest both for fundamental research and applications in the past decade. In photonic crystal cavities, the leakage to optical modes is strongly reduced, which increases the spontaneous emission coupling factor, β. This is a crucial parameter for the threshold characteristics of lasers. With increasing β, the well-known step-like threshold behavior becomes smoother. Although the smooth lasing transitions of photonic crystal nanolasers were observed and fitted by traditional rate equation models [1], a systematic comparison between experiments and more advanced semiconductor models of photonic crystal nanolasers is still missing [2]. The goal of this work is to get a deep understanding of the quantum dots based nanocavity lasers by comparing experiments to theory.","PeriodicalId":6331,"journal":{"name":"2011 Conference on Lasers and Electro-Optics Europe and 12th European Quantum Electronics Conference (CLEO EUROPE/EQEC)","volume":"17 1","pages":"1-1"},"PeriodicalIF":0.0,"publicationDate":"2012-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82256929","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
N. Behbood, B. Dubost, M. Napolitano, M. Koschorreck, R. Sewell, G. Tóth, M. Mitchell
We report on an experiment underway for generating a singlet state in a cold atomic ensemble. The experiment is based on a recent proposal to generate these states by applying a quantum non-demolition (QND) measurement and feedback to an unpolarized ensemble [1]. Our criteria for generating the singlet state is the spin squeezing parameter equation where Fi are the components of the collective angular momentum, N is the number of atoms and f is the spin of a single particle. Any state with ξs < 1 is an entangled state [2]. Our procedure, described bellow, will lead to a highly entangled state with ξs ≪ 1 starting from a non-entangled state with ξ ∼ 1.
{"title":"Generation of a macroscopic singlet state in an atomic ensemble","authors":"N. Behbood, B. Dubost, M. Napolitano, M. Koschorreck, R. Sewell, G. Tóth, M. Mitchell","doi":"10.1364/QIM.2012.QM1B.2","DOIUrl":"https://doi.org/10.1364/QIM.2012.QM1B.2","url":null,"abstract":"We report on an experiment underway for generating a singlet state in a cold atomic ensemble. The experiment is based on a recent proposal to generate these states by applying a quantum non-demolition (QND) measurement and feedback to an unpolarized ensemble [1]. Our criteria for generating the singlet state is the spin squeezing parameter equation where Fi are the components of the collective angular momentum, N is the number of atoms and f is the spin of a single particle. Any state with ξs < 1 is an entangled state [2]. Our procedure, described bellow, will lead to a highly entangled state with ξs ≪ 1 starting from a non-entangled state with ξ ∼ 1.","PeriodicalId":6331,"journal":{"name":"2011 Conference on Lasers and Electro-Optics Europe and 12th European Quantum Electronics Conference (CLEO EUROPE/EQEC)","volume":"30 1","pages":"1-1"},"PeriodicalIF":0.0,"publicationDate":"2012-03-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73474241","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2011-08-28DOI: 10.1109/IQEC-CLEO.2011.6193996
A. Jechow, M. Petrasiunas, M. Pullen, J. Canning, M. Stevenson, P. Westbrook, K. Feder, D. Kielpinski
Trapped ions are a major candidate technology for scalable quantum computation. However, current methods for performing quantum logic gates with trapped ions are limited to gate times of about 10 µs. This drawback is overcome in a recently proposed scheme that uses pairs of counter-propagating π-pulses, resonant with an allowed ion transition, where the time needed for a gate operation is inversely proportional to the laser repetition rate [1]. Our MOPA architecture allows scaling to high repetition rate at constant pulse energy.
{"title":"High-power ultrafast laser source with 300 MHz repetition rate for trapped-ion quantum logic","authors":"A. Jechow, M. Petrasiunas, M. Pullen, J. Canning, M. Stevenson, P. Westbrook, K. Feder, D. Kielpinski","doi":"10.1109/IQEC-CLEO.2011.6193996","DOIUrl":"https://doi.org/10.1109/IQEC-CLEO.2011.6193996","url":null,"abstract":"Trapped ions are a major candidate technology for scalable quantum computation. However, current methods for performing quantum logic gates with trapped ions are limited to gate times of about 10 µs. This drawback is overcome in a recently proposed scheme that uses pairs of counter-propagating π-pulses, resonant with an allowed ion transition, where the time needed for a gate operation is inversely proportional to the laser repetition rate [1]. Our MOPA architecture allows scaling to high repetition rate at constant pulse energy.","PeriodicalId":6331,"journal":{"name":"2011 Conference on Lasers and Electro-Optics Europe and 12th European Quantum Electronics Conference (CLEO EUROPE/EQEC)","volume":"40 1","pages":"1-1"},"PeriodicalIF":0.0,"publicationDate":"2011-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89000557","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2011-05-22DOI: 10.1109/CLEOE.2011.5943482
A. Belardini1, M. C. Larciprete1, M. Centini, E. Fazio, C. Sibilia, D. Chiappe, C. Martella, A. Toma, F. B. de Mongeot
Metal nanostructures supported on dielectric substrates have attracted great interest as building blocks of nanoscale optical devices such nano-plasmonic devices or planar metamaterials. In this framework artificial circular dichroism [1] is investigated for developing novel devices for active polarization controllers, like rotators and modulators and high efficient molecular sensors. Here we report the experimental observation of nonlinear extrinsic chirality [2] (circular dichroism) of the second harmonic (SH) field generated by self-organized gold nanowire arrays with sub-wavelength periodicity [3]. In this material the chirality arises from the curvature of the self-assembled wires, producing a lack of symmetry at oblique incidence [2]. Such circular dichroism in the SH field is the evident signature of the sample morphology and can be used in order to develop more efficient molecular sensors, based on metal enhanced fluorescence or surface enhanced Raman scattering.
{"title":"Nonlinear circular dichroism in self-organized metal nanowires arrays","authors":"A. Belardini1, M. C. Larciprete1, M. Centini, E. Fazio, C. Sibilia, D. Chiappe, C. Martella, A. Toma, F. B. de Mongeot","doi":"10.1109/CLEOE.2011.5943482","DOIUrl":"https://doi.org/10.1109/CLEOE.2011.5943482","url":null,"abstract":"Metal nanostructures supported on dielectric substrates have attracted great interest as building blocks of nanoscale optical devices such nano-plasmonic devices or planar metamaterials. In this framework artificial circular dichroism [1] is investigated for developing novel devices for active polarization controllers, like rotators and modulators and high efficient molecular sensors. Here we report the experimental observation of nonlinear extrinsic chirality [2] (circular dichroism) of the second harmonic (SH) field generated by self-organized gold nanowire arrays with sub-wavelength periodicity [3]. In this material the chirality arises from the curvature of the self-assembled wires, producing a lack of symmetry at oblique incidence [2]. Such circular dichroism in the SH field is the evident signature of the sample morphology and can be used in order to develop more efficient molecular sensors, based on metal enhanced fluorescence or surface enhanced Raman scattering.","PeriodicalId":6331,"journal":{"name":"2011 Conference on Lasers and Electro-Optics Europe and 12th European Quantum Electronics Conference (CLEO EUROPE/EQEC)","volume":"24 1","pages":"1-1"},"PeriodicalIF":0.0,"publicationDate":"2011-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73477536","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2011-05-22DOI: 10.1109/CLEOE.2011.5942757
O. Mhibik, D. Paboeuf, C. Drag, F. Bretenaker
Quantum manipulation using the optical transition (3H4→1D2) of Pr3+ embedded in solid state host materials requires a visible source emitting at 606 nm with a linewidth at the kHz level [1]. In a previous work, we have reported the stabilization of a continuous wave intracavity frequency doubled singly resonant optical parametric oscillator (cw-SHG-SRO) by locking it onto the side of the transmission fringe of a medium finesse Fabry-Perot (FP) cavity [2]. In this scheme, the signal transmitted by the FP cavity was not only sensitive to any frequency fluctuation but also to any change in the source power, which can be misinterpreted as a frequency fluctuation.
{"title":"The kHz level stabilization of an intracavity doubled continuous wave optical parametric oscillator using Pound-Drever-Hall scheme","authors":"O. Mhibik, D. Paboeuf, C. Drag, F. Bretenaker","doi":"10.1109/CLEOE.2011.5942757","DOIUrl":"https://doi.org/10.1109/CLEOE.2011.5942757","url":null,"abstract":"Quantum manipulation using the optical transition (3H4→1D2) of Pr3+ embedded in solid state host materials requires a visible source emitting at 606 nm with a linewidth at the kHz level [1]. In a previous work, we have reported the stabilization of a continuous wave intracavity frequency doubled singly resonant optical parametric oscillator (cw-SHG-SRO) by locking it onto the side of the transmission fringe of a medium finesse Fabry-Perot (FP) cavity [2]. In this scheme, the signal transmitted by the FP cavity was not only sensitive to any frequency fluctuation but also to any change in the source power, which can be misinterpreted as a frequency fluctuation.","PeriodicalId":6331,"journal":{"name":"2011 Conference on Lasers and Electro-Optics Europe and 12th European Quantum Electronics Conference (CLEO EUROPE/EQEC)","volume":"25 1","pages":"1-1"},"PeriodicalIF":0.0,"publicationDate":"2011-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73635507","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2011-05-22DOI: 10.1109/CLEOE.2011.5943272
J. Bertolotti, K. Vynck, D. Wiersma
In the textbook case of normal diffusion, transport is described as a randomwalk to which all the steps give the same contribution (Brownian motion). Superdiffusion occurs when the transport is dominated by a few, very large steps (Lévy flights). In this regime the variance of the step length distribution diverges and the mean square displacement grows faster than linear with time [1]. Previous works have evidenced the peculiar statistical properties of Lévy motions and shown that several features of real experiments, such as properly defined boundary conditions, are nontrivial to implement [2], making the description of observable quantities nearly impossible.
{"title":"Multiple scattering of light in finite-size superdiffusive media","authors":"J. Bertolotti, K. Vynck, D. Wiersma","doi":"10.1109/CLEOE.2011.5943272","DOIUrl":"https://doi.org/10.1109/CLEOE.2011.5943272","url":null,"abstract":"In the textbook case of normal diffusion, transport is described as a randomwalk to which all the steps give the same contribution (Brownian motion). Superdiffusion occurs when the transport is dominated by a few, very large steps (Lévy flights). In this regime the variance of the step length distribution diverges and the mean square displacement grows faster than linear with time [1]. Previous works have evidenced the peculiar statistical properties of Lévy motions and shown that several features of real experiments, such as properly defined boundary conditions, are nontrivial to implement [2], making the description of observable quantities nearly impossible.","PeriodicalId":6331,"journal":{"name":"2011 Conference on Lasers and Electro-Optics Europe and 12th European Quantum Electronics Conference (CLEO EUROPE/EQEC)","volume":"28 1","pages":"1-1"},"PeriodicalIF":0.0,"publicationDate":"2011-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73937993","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2011-05-22DOI: 10.1109/CLEOE.2011.5943004
S. Berry, J. Gates, W. Brocklesby
Multi-mode photonic lightwave circuits (PLCs) provide new avenues for extending the performance of single mode systems. As an example, they can potentially provide increased bandwidth by multiplexing information into different waveguide modes[1]. For practical applications of multi-mode PLCs to be developed, a measurement technique is required to investigate detailed mode profiles and propagation constants in complex circuits. Photon scanning tunnelling microscopy (PSTM) provides a means of experimentally tracking the femtosecond inter-modal delays observed in PLCs with the ability to discriminate modes by their spatial profiles inside the waveguide.
{"title":"Direct spatial-temporal discrimination of modes in a photonic lightwave circuit using photon scanning tunnelling microscopy","authors":"S. Berry, J. Gates, W. Brocklesby","doi":"10.1109/CLEOE.2011.5943004","DOIUrl":"https://doi.org/10.1109/CLEOE.2011.5943004","url":null,"abstract":"Multi-mode photonic lightwave circuits (PLCs) provide new avenues for extending the performance of single mode systems. As an example, they can potentially provide increased bandwidth by multiplexing information into different waveguide modes[1]. For practical applications of multi-mode PLCs to be developed, a measurement technique is required to investigate detailed mode profiles and propagation constants in complex circuits. Photon scanning tunnelling microscopy (PSTM) provides a means of experimentally tracking the femtosecond inter-modal delays observed in PLCs with the ability to discriminate modes by their spatial profiles inside the waveguide.","PeriodicalId":6331,"journal":{"name":"2011 Conference on Lasers and Electro-Optics Europe and 12th European Quantum Electronics Conference (CLEO EUROPE/EQEC)","volume":"100 1","pages":"1-1"},"PeriodicalIF":0.0,"publicationDate":"2011-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74026985","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2011-05-22DOI: 10.1109/CLEOE.2011.5942613
H. Oda, N. Hamada, A. Yamanaka, N. Ozaki, N. Ikeda, Y. Sugimoto
Photonic crystals are very suitable for controlling radiation field and propagation characterization of light. As an important application, it is ultra compact and ultrafast optical integrated circuits (OIC) based on photonic crystals slab waveguides (PC-WGs) composing of the line-defects [1, 2]. The PC-WG is also attractive for laser lasing, because very small group velocity of near the Brillouin zone (BZ) edge should enhance interactions between the radiation field and matter. Indeed, the lasing spectrum has been observed from optically pumped InAs-quantum dots (InAs-QDs) embedded in PC-WG of the multimode W3 type (three rows missing line-defect) [3]. In the present study, we observe laser action in InAs-QDs PC-WG of the single-mode W1 type (single row missing line-defect).
{"title":"InAs quantum-dots laser utilizing GaAs W1 type photonic-crystal slab line-defect waveguide","authors":"H. Oda, N. Hamada, A. Yamanaka, N. Ozaki, N. Ikeda, Y. Sugimoto","doi":"10.1109/CLEOE.2011.5942613","DOIUrl":"https://doi.org/10.1109/CLEOE.2011.5942613","url":null,"abstract":"Photonic crystals are very suitable for controlling radiation field and propagation characterization of light. As an important application, it is ultra compact and ultrafast optical integrated circuits (OIC) based on photonic crystals slab waveguides (PC-WGs) composing of the line-defects [1, 2]. The PC-WG is also attractive for laser lasing, because very small group velocity of near the Brillouin zone (BZ) edge should enhance interactions between the radiation field and matter. Indeed, the lasing spectrum has been observed from optically pumped InAs-quantum dots (InAs-QDs) embedded in PC-WG of the multimode W3 type (three rows missing line-defect) [3]. In the present study, we observe laser action in InAs-QDs PC-WG of the single-mode W1 type (single row missing line-defect).","PeriodicalId":6331,"journal":{"name":"2011 Conference on Lasers and Electro-Optics Europe and 12th European Quantum Electronics Conference (CLEO EUROPE/EQEC)","volume":"6 1","pages":"1-1"},"PeriodicalIF":0.0,"publicationDate":"2011-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72754600","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2011-05-22DOI: 10.1109/CLEOE.2011.5943104
A. Cabasse, G. Martel, T. Nguyen, J. Oudar, S. Maine, Y. Battie, B. Attal‐Tretout
Ultrashort pulse laser sources are deployed in a wide variety of applications ranging from basic scientific research and metrology to eye surgery and material processing. The majority of fiber lasers produce ultrashort pulses thanks to nonlinear optical elements called saturable absorbers (SA). Currently, multiple quantum wells (MQW-SA) structures are regularly used as SA. Recently, at 1.5 µm, we report the highest pulse energy extracted from a fiber oscillator passively mode-locked by MQW-SA [1]. The discovery of the nonlinear optical behaviour of carbon nanotubes (CNT-SA) makes them attractive materials for replacing MQW-SA [2].
{"title":"Comparison between multiple quantum wells and carbon nanotubes to generate high power in mode-locked fiber oscillator","authors":"A. Cabasse, G. Martel, T. Nguyen, J. Oudar, S. Maine, Y. Battie, B. Attal‐Tretout","doi":"10.1109/CLEOE.2011.5943104","DOIUrl":"https://doi.org/10.1109/CLEOE.2011.5943104","url":null,"abstract":"Ultrashort pulse laser sources are deployed in a wide variety of applications ranging from basic scientific research and metrology to eye surgery and material processing. The majority of fiber lasers produce ultrashort pulses thanks to nonlinear optical elements called saturable absorbers (SA). Currently, multiple quantum wells (MQW-SA) structures are regularly used as SA. Recently, at 1.5 µm, we report the highest pulse energy extracted from a fiber oscillator passively mode-locked by MQW-SA [1]. The discovery of the nonlinear optical behaviour of carbon nanotubes (CNT-SA) makes them attractive materials for replacing MQW-SA [2].","PeriodicalId":6331,"journal":{"name":"2011 Conference on Lasers and Electro-Optics Europe and 12th European Quantum Electronics Conference (CLEO EUROPE/EQEC)","volume":"30 1","pages":"1-1"},"PeriodicalIF":0.0,"publicationDate":"2011-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72903826","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2011-05-22DOI: 10.1109/CLEOE.2011.5943186
S. Guillemet, D. Kinet, F. Narbonneau, Y. Hernandez, D. Giannone
We present a high power all-in-fibre Raman laser delivering 20.6 W at 1270 nm with an efficiency of 70%. This laser can be used for medical applications like photodynamic therapy of cancer. To our knowledge, this is the highest power ever reported in literature for a Raman laser based on phosphosilicate fibre.
{"title":"High power all-in-fibre continuous wave Raman laser based on phosphosilicate fibre","authors":"S. Guillemet, D. Kinet, F. Narbonneau, Y. Hernandez, D. Giannone","doi":"10.1109/CLEOE.2011.5943186","DOIUrl":"https://doi.org/10.1109/CLEOE.2011.5943186","url":null,"abstract":"We present a high power all-in-fibre Raman laser delivering 20.6 W at 1270 nm with an efficiency of 70%. This laser can be used for medical applications like photodynamic therapy of cancer. To our knowledge, this is the highest power ever reported in literature for a Raman laser based on phosphosilicate fibre.","PeriodicalId":6331,"journal":{"name":"2011 Conference on Lasers and Electro-Optics Europe and 12th European Quantum Electronics Conference (CLEO EUROPE/EQEC)","volume":"8 1","pages":"1-1"},"PeriodicalIF":0.0,"publicationDate":"2011-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73110255","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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