APL: Lasers, Optics, and Optoelectronics http://scitation.aip.org/ APL: Lasers, Optics, and Optoelectronics Effect of polarization on spectral switches in the diffraction of stochastic electromagnetic beams http://link.aip.org/link/?APL/95/181112/1&agg=rss Liuzhan Pan, Zhiguo Zhao, Chaoliang Ding, and Baida Lu<br/> We consider the stochastic electromagnetic Gaussian Schell-model (EGSM) beam and show that the polarization of stochastic electromagnetic EGSM beams in the source plane affect spectral switches of diffracted stochastic electromagnetic EGSM beams in the far field. For two cases of fully coherent and ... [Appl. Phys. Lett. 95, 181112 (2009)] published Fri Nov 6, 2009. Birefringence-induced mode-dependent tuning of liquid crystal infiltrated InGaAsP photonic crystal nanocavities http://link.aip.org/link/?APL/95/181111/1&agg=rss M. A. Dundar, H. H. J. E. Kicken, A. Yu. Silov, R. Notzel, F. Karouta et al.<br/> Mode-dependent shifts of resonant frequencies of cavities in liquid crystal (LC) infiltrated planar photonic crystals (PhC) are experimentally observed when the temperature is varied across the LC ordering transition. The shifts can be in opposite directions, even for two very similar nearly degener ... [Appl. Phys. Lett. 95, 181111 (2009)] published Fri Nov 6, 2009. Microbubble-enhanced ultrasound-modulated fluorescence in a turbid medium http://link.aip.org/link/?APL/95/181113/1&agg=rss Baohong Yuan, Yuan Liu, Patrick M. Mehl, and Joseph Vignola<br/> The feasibility of using ultrasound to modulate fluorescence in a turbid medium is still in debate due to the difficulty of detecting the modulated signal. We have demonstrated a system that could detect the weak signals of ultrasound-modulated fluorescence (UMF) by using a broadband lock-in amplifi ... [Appl. Phys. Lett. 95, 181113 (2009)] published Fri Nov 6, 2009. Polarization entanglement with graded-index lenses http://link.aip.org/link/?APL/95/181110/1&agg=rss Giuseppe Vallone, Gaia Donati, Francesco De Martini, and Paolo Mataloni<br/> By using an optical device based on the integration of a graded-index (GRIN) rod lens and a single-mode optical fiber we efficiently collected photon pairs generated by spontaneous parametric down-conversion. We show that this system preserves the polarization entanglement of the two-photon states. ... [Appl. Phys. Lett. 95, 181110 (2009)] published Fri Nov 6, 2009. Engineering single photon emitters by ion implantation in diamond http://link.aip.org/link/?APL/95/181109/1&agg=rss B. Naydenov, R. Kolesov, A. Batalov, J. Meijer, S. Pezzagna et al.<br/> Diamond provides unique technological platform for quantum technologies including quantum computing and communication. Controlled fabrication of optically active defects is a key element for such quantum toolkit. Here we report the production of single color centers emitting in the blue spectral reg ... [Appl. Phys. Lett. 95, 181109 (2009)] published Thu Nov 5, 2009. Ultrafast imaging of photoelectron packets generated from graphite surface http://link.aip.org/link/?APL/95/181108/1&agg=rss Ramani K. Raman, Zhensheng Tao, Tzong-Ru Han, and Chong-Yu Ruan<br/> We present an electron projection imaging method to study the ultrafast evolution of photoelectron density distribution and transient fields near the surface. The dynamical profile of the photoelectrons from graphite reveals an origin of a thermionic emission, followed by an adiabatic process leadin ... [Appl. Phys. Lett. 95, 181108 (2009)] published Thu Nov 5, 2009. Bistable twisted-bend and twisted-nematic liquid crystal display http://link.aip.org/link/?APL/95/181107/1&agg=rss Y. W. Li and H. S. Kwok<br/> Bistability of twisted-bend and twisted configuration is found. It is based on the elastic and topological inequivalency of director orientation. Multiple states of minimum local energy exist, with appropriate boundary conditions. The effects of elastic constants, d/P ratio and pretilt angle are als ... [Appl. Phys. Lett. 95, 181107 (2009)] published Thu Nov 5, 2009. Controlling the spectrum of x-rays generated in a laser-plasma accelerator by tailoring the laser wavefront http://link.aip.org/link/?APL/95/181106/1&agg=rss S. P. D. Mangles, G. Genoud, S. Kneip, M. Burza, K. Cassou et al.<br/> By tailoring the wavefront of the laser pulse used in a laser-wakefield accelerator, we show that the properties of the x-rays produced due to the electron beam's betatron oscillations in the plasma can be controlled. By creating a wavefront with coma, we find that the critical energy of the synchro ... [Appl. Phys. Lett. 95, 181106 (2009)] published Wed Nov 4, 2009. Flexible metamaterials for wireless strain sensing http://link.aip.org/link/?APL/95/181105/1&agg=rss Rohat Melik, Emre Unal, Nihan Kosku Perkgoz, Christian Puttlitz, and Hilmi Volkan Demir<br/> We proposed and demonstrated flexible metamaterial-based wireless strain sensors that include arrays of split ring resonators (SRRs) to telemetrically measure strain. For these metamaterial sensors, we showed that a flexible substrate (e.g., Kapton tape) delivers greater sensitivity and a more linea ... [Appl. Phys. Lett. 95, 181105 (2009)] published Wed Nov 4, 2009. Optical position clamping with predictive control http://link.aip.org/link/?APL/95/181104/1&agg=rss Heikki Ojala, Anders Korsback, Anders E. Wallin, and Edward Haeggstrom<br/> We increase the effective stiffness of optical tweezers by position clamping a polystyrene bead with a predictive feedback control algorithm. This algorithm mitigates the effect of feedback loop delay. Hence, higher gain than with proportional control can be employed, which results in higher effecti ... [Appl. Phys. Lett. 95, 181104 (2009)] published Wed Nov 4, 2009. Near-field imaging of femtosecond laser ablated sub-lambda/4 holes in lithium niobate http://link.aip.org/link/?APL/95/181103/1&agg=rss Airan Rodenas, Jorge Lamela, Daniel Jaque, Gines Lifante, Francisco Jaque et al.<br/> We report on the direct femtosecond laser ablation of sub-lambda/4 (80250 nm) holes in LiNbO crystals and on its local near-field imaging. We show that the near-field transmission of holes can feature an attenuation of ~75% at hole central position, and a ~20% transmission enhancement at its sides. ... [Appl. Phys. Lett. 95, 181103 (2009)] published Mon Nov 2, 2009. Thermal-induced refractive-index planar waveguide laser http://link.aip.org/link/?APL/95/181102/1&agg=rss Hongxiang Kang<!--orlang--> (&#x5EB7;&#x5B8F;&#x5411;)<!--orlang-->, Haitao Zhang<!--orlang--> (&#x5F20;&#x6D77;&#x6D9B;)<!--orlang-->, and Dongsheng Wang<!--orlang--> (&#x738B;&#x4E1C;&#x751F;)<!--orlang--><br/> The feasibility of a thermal-induced refractive-index planar waveguide laser was demonstrated. The condition for the guided modes to be confined in the gain region was calculated. A thermal-induced refractive-index planar waveguide laser was made simply by pumping a thin center layer of a slab cryst ... [Appl. Phys. Lett. 95, 181102 (2009)] published Mon Nov 2, 2009. Electrically tunable terahertz quantum-cascade laser with a heterogeneous active region http://link.aip.org/link/?APL/95/181101/1&agg=rss Suraj P. Khanna, Mohammed Salih, Paul Dean, A. Giles Davies, and Edmund H. Linfield<br/> We demonstrate experimentally a terahertz frequency quantum-cascade laser which can be tuned electronically, in a step-wise manner from typically 3.07 to 3.40 THz, by changing the applied electric field across the device. To achieve this, the gallium growth rate was successively reduced during growt ... [Appl. Phys. Lett. 95, 181101 (2009)] published Mon Nov 2, 2009. Conoscopic observation of director reorientation during Poiseuille flow of a nematic liquid crystal http://link.aip.org/link/?APL/95/171114/1&agg=rss C. J. Holmes, S. L. Cornford, and J. R. Sambles<br/> Director reorientation under pressure driven (Poiseuille) flow is observed conoscopically for the liquid crystal 5CB aligned at an azimuthal angle of 45 degrees to the direction of flow. A polyimide surface treatment (AL 1254) is used to promote planar homogeneous alignment and rubbed to produce an ... [Appl. Phys. Lett. 95, 171114 (2009)] published Fri Oct 30, 2009. Plasmonic waveguide as an efficient transducer for high-density data storage http://link.aip.org/link/?APL/95/171112/1&agg=rss D. O'Connor, M. McCurry, B. Lafferty, and A. V. Zayats<br/> A design of high optical throughput nanoscale light sources has been proposed based on plasmonic wedge waveguides. It provides localization of the 1500 nm wavelength light at the output of less than 30 x 30 nm area at about 80% coupling efficiency from a dielectric loaded surface plasmon polariton ... [Appl. Phys. Lett. 95, 171112 (2009)] published Fri Oct 30, 2009. Cavity-enhanced photocurrent generation by 1.55 [mu]m wavelengths linear absorption in a p-i-n diode embedded silicon microring resonator http://link.aip.org/link/?APL/95/171111/1&agg=rss Hui Chen, Xianshu Luo, and Andrew W. Poon<br/> We demonstrate 20-fold cavity-enhanced photocurrent generation in 1.55 [mu]m wavelengths in a p-i-n diode embedded silicon microring resonator with Q factor of 8000. The on-resonance wavelength shows linear responsivity of 0.12 mA/W upon 0 V bias and 0.25 mA/W upon 15 V bias. We attribute the linea ... [Appl. Phys. Lett. 95, 171111 (2009)] published Fri Oct 30, 2009. Terahertz microfluidic sensor based on a parallel-plate waveguide resonant cavity http://link.aip.org/link/?APL/95/171113/1&agg=rss Rajind Mendis, Victoria Astley, Jingbo Liu, and Daniel M. Mittleman<br/> We describe a terahertz optical resonator that is ideally suited for highly sensitive and noninvasive refractive-index monitoring. The resonator is formed by machining a rectangular groove into one plate of a parallel-plate waveguide, and is excited using the lowest-order transverse-electric (TE) wa ... [Appl. Phys. Lett. 95, 171113 (2009)] published Fri Oct 30, 2009. All-optical phase modulations in a silicon wire waveguide at ultralow light levels http://link.aip.org/link/?APL/95/171110/1&agg=rss Nobuyuki Matsuda<!--orlang--> (&#x677E;&#x7530;&#x4FE1;&#x5E78;)<!--orlang-->, Ryosuke Shimizu<!--orlang--> (&#x6E05;&#x6C34;&#x4EAE;&#x4ECB;)<!--orlang-->, Yasuyoshi Mitsumori<!--orlang--> (&#x4E09;&#x68EE;&#x5EB7;&#x7FA9;)<!--orlang-->, Hideo Kosaka<!--orlang--> (&#x5C0F;&#x5742;&#x82F1;&#x7537;)<!--orlang-->, Aya Sato<!--orlang--> (&#x4F50;&#x85E4;&#x7DBE;&#x8036;)<!--orlang--> et al.<br/> Cross-phase modulation (XPM) in a silicon wire waveguide at 1.55 [mu]m telecom band was studied down to ultralow light levels. In the low-power regime, we found that free-carrier dispersion as well as the optical Kerr effect contributes to the XPM. Possible mechanisms of the low-power XPM are discu ... [Appl. Phys. Lett. 95, 171110 (2009)] published Fri Oct 30, 2009. Pulsed-laser printing of organic thin-film transistors http://link.aip.org/link/?APL/95/171109/1&agg=rss Ludovic Rapp, Abdou Karim Diallo, Anne Patricia Alloncle, Christine Videlot-Ackermann, Frederic Fages et al.<br/> Organic thin-film transistors have been fabricated using laser-induced forward transfer as spatially resolved laser-printing method. Using this technique, source and drain electrodes were deposited from silver nanoparticle ink and the copper phthalocyanine (CuPc) was used to form the active layer. B ... [Appl. Phys. Lett. 95, 171109 (2009)] published Thu Oct 29, 2009. A scattering model for surface-textured thin films http://link.aip.org/link/?APL/95/171108/1&agg=rss Klaus Jager and Miro Zeman<br/> We present a mathematical model that relates the surface morphology of randomly surface-textured thin films with the intensity distribution of scattered light. The model is based on the first order Born approximation [see e.g., M. Born and E. Wolf, Principles of Optics, 7th ed. (Cambridge University ... [Appl. Phys. Lett. 95, 171108 (2009)] published Thu Oct 29, 2009. Soliton source generation in a few-mode tellurite microstructure fiber http://link.aip.org/link/?APL/95/171107/1&agg=rss Xin Yan, Guanshi Qin, Meisong Liao, Takenobu Suzuki, Atsushi Mori et al.<br/> We report broad near-infrared soliton and associated dispersive wave source generation (12281867 nm) and tunable green third harmonic generation (528542 nm) by LP mode excitation in a few-mode tellurite microstructure fiber pumped by a 1557 nm femtosecond fiber laser. The fiber presents a wide ran ... [Appl. Phys. Lett. 95, 171107 (2009)] published Thu Oct 29, 2009. Influence of GeSi interfacial layer on GeGe optical phonon mode in SiO films embedded with Ge nanocrystals http://link.aip.org/link/?APL/95/171105/1&agg=rss L. Z. Liu, F. Gao, X. L. Wu, T. H. Li, and Paul K. Chu<br/> The GeGe optical phonon peak at 300 cm acquired from amorphous SiO films embedded with Ge nanocrystals by Raman scattering is sensitive to the Si content. When the Si concentration is high, a thin GeSi interfacial layer forms around the Ge nanocrystals. A tensile stress is produced to partially off ... [Appl. Phys. Lett. 95, 171105 (2009)] published Wed Oct 28, 2009. Experimental observation of subluminal and superluminal light propagation in rhodamine 6G-doped polymethyl methacrylate http://link.aip.org/link/?APL/95/171106/1&agg=rss Wending Zhang, Feng Gao, Guoquan Zhang, Wei Li, Xinzheng Zhang et al.<br/> Nondegenerate two-wave coupling process and group velocity change in the paraxial part of an intensity-modulated and focused transverse electromagnetic beam (TEM beam in the article) was observed in the rhodamine 6G(R6G)-doped polymethyl methacrylate (PMMA) but not in the pure PMMA. The typical supe ... [Appl. Phys. Lett. 95, 171106 (2009)] published Wed Oct 28, 2009. Impact of high-order surface plasmon modes of metal nanoparticles on enhancement of optical emission http://link.aip.org/link/?APL/95/171103/1&agg=rss G. Sun, J. B. Khurgin, and C. C. Yang<br/> We consider the impact of high-order surface plasmon modes supported by the metal nanoparticles on the efficiency enhancement of optical emission. Using the example of Au nanosphere embedded in the GaN dielectric, we show that for an emitter with certain original radiative efficiency, placing the em ... [Appl. Phys. Lett. 95, 171103 (2009)] published Tue Oct 27, 2009. Strongly birefringent metamaterials as negative index terahertz wave plates http://link.aip.org/link/?APL/95/171104/1&agg=rss P. Weis, O. Paul, C. Imhof, R. Beigang, and M. Rahm<br/> We report an alternative approach for the design and fabrication of thin wave plates with high transmission in the terahertz regime. The wave plates are based on strongly birefringent cut-wire-pair metamaterials that exhibit refractive indices of opposite signs for orthogonal polarization components ... [Appl. Phys. Lett. 95, 171104 (2009)] published Tue Oct 27, 2009. Otto-coupled surface plasmons in a liquid crystal cell http://link.aip.org/link/?APL/95/171102/1&agg=rss Lizhen Ruan, Fuzi Yang, and J. R. Sambles<br/> Surface plasmons on silver in the visible domain are excited using a several micron thick layer of liquid crystal as the optical tunnel barrier. This thickness is possible when the orientation of the director in the liquid crystal varies from homeotropic at the entrance surface (against the coupling ... [Appl. Phys. Lett. 95, 171102 (2009)] published Mon Oct 26, 2009. Refractive index dispersion deduced from lasing modes in ZnO microtetrapods http://link.aip.org/link/?APL/95/171101/1&agg=rss V. V. Ursaki, V. V. Zalamai, I. M. Tiginyanu, A. Burlacu, E. V. Rusu et al.<br/> High optical quality, well end leg faceted ZnO microtetrapods sustaining lasing modes with quality factors of 25003000 have been grown by carbothermal chemical vapor deposition. It is shown that lasing is due to longitudinal FabryPerot modes in individual tetrapod legs and the analysis of the wavele ... [Appl. Phys. Lett. 95, 171101 (2009)] published Mon Oct 26, 2009.