Results 51 to 60 of about 20,626 (216)

Cascaded four-wave mixing in tapered plasmonic nanoantenna

, 2012
We study theoretically the cascaded four-wave mixing (FWM) in broadband tapered plasmonic nanoantennas and demonstrate a 300-fold increase in nonlinear frequency conversion detected in the main lobe of the nanoantenna far-field pattern.
A. E. Miroshnichenko, Abb, Bharadwaj, Danckwerts, Grady, Harutyunyan, Hentschel, Humphrey, I. S. Maksymov, Ko, Lippitz, Maksymov, Maksymov, Maksymov, Maksymov, Maksymov, Maksymov, Minovich, Navarro-Cia, Palomba, Pavlov, Schumacher, Slablab, Stockman, Yu. S. Kivshar   +24 more
core   +1 more source

Measurement of the stimulated carrier lifetime in semiconductor optical amplifiers by four-wave mixing of polarized ASE noise [PDF]

, 1997
We present a simple experiment aimed at measuring the stimulated carrier lifetime in semiconductor optical amplifiers (SOA's). The technique relies on polarization-resolved nearly degenerate four-wave mixing (FWM) of a laser source with an amplified ...
Hunziker, Guido, Koren, Uzi, Paiella, Roberto, Vahala, Kerry J.   +3 more
core   +1 more source

The Impact and Reliability of Tissue Segmentation on In Vivo Magnetic Resonance Spectroscopy Metabolite Quantification

Magnetic Resonance in Medicine, EarlyView.
ABSTRACT Purpose Quantification of metabolite concentrations using MRS requires tissue‐dependent signal corrections. Accurate estimation of voxel tissue composition is therefore essential. Commonly used brain tissue segmentation tools differ in their algorithms and implementation, potentially introducing variability in MRS‐derived concentration ...
Jessica Archibald, Kay Chioma Igwe, Antonia Kaiser, Karl Landheer, Jaimie Lee, John L. K. Kramer, Aaron T. Gudmundson, Helge J. Zöllner, Georg Oeltzschner, Candace C. Fleischer, Niklaus Zölch, Jamie Near, Mark Mikkelsen   +12 more
wiley   +1 more source

Exceptionally Slow Rise in Differential Reflectivity Spectra of Excitons in GaN: Effect of Excitation-induced Dephasing

, 2003
Femtosecond pump-probe (PP) differential reflectivity spectroscopy (DRS) and four-wave mixing (FWM) experiments were performed simultaneously to study the initial temporal dynamics of the exciton line-shapes in GaN epilayers.
A. J. Fischer, A. Shikanai, A.J. Fischer, A.J. Fischer, C. J. Stanton, C.-K. Sun, C.-K. Sun, C.-K. Sun, C.-K. Sun, C.H. Brito Cruz, C.J. Stanton, D. S. Kim, D.C. Reynolds, D.S. Kim, D.W. Bailey, E.J. Mayer, H. Wang, J. J. Song, J. Kenrow, J.A. Kenrow, J.S. Yahng, K. El Sayed, K. El Sayed, K. Leo, K.J. Yee, M. Wegener, P. Langot, R. Tommasi, R. Zimmermann, S. Pau, S. Zollner, S. Zollner, S.W. Koch, T. Aoki, Y. D. Jho, Y.D. Jho, Y.D. Jho, Y.Z. Hu, Y.Z. Hu   +38 more
core   +1 more source

The Impact of Midwife Experience and Time of Birth on the Risk of Obstetric Anal Sphincter Injuries (OASIS)

Birth, EarlyView.
Background: Obstetric anal sphincter injuries (OASIS) are a significant complication of vaginal birth. Methods: This retrospective cohort included 13,651 term spontaneous vaginal deliveries at a single medical center (2020‐2025). Midwife experience (early, mid, and highly experienced), shift timing, and OASIS incidence were analyzed.
Raneen Abu Shqara, Susana Mustafa Mikhail, Sari Nahir Biderman, Nadir Ganem, Lior Lowenstein, Maya Frank Wolf   +5 more
wiley   +1 more source

Enhanced nonlinearity of four-wave mixing via Rydberg–Rydberg interactions

New Journal of Physics, 2022
We investigate the four-wave mixing (FWM) nonlinearity in an ensemble of cold Rydberg atoms with each of them regarded as a double-ladder system. The interaction is studied from the view of generating a signal field in virtue of three applied lasers ...
Xiao-Jun Zhang, Huan Chang, Jia-Yao Huo, Jin-Hui Wu   +3 more
doaj   +1 more source

Four wave mixing spectroscopy of quantum dot molecules

, 2007
We study theoretically the nonlinear four wave mixing (FWM) response of an ensemble of coupled pairs of quantum dots (quantum dot molecules). We discuss the shape of the FWM echo signal depending on the parameters of the ensemble: the statistics of ...
Machnikowski, P., Sitek, A.
core   +1 more source

A proposal for highly tunable optical parametric oscillation in silicon micro-resonators [PDF]

, 2008
We propose a novel scheme for continuous-wave pumped optical parametric oscillation (OPO) inside silicon micro-resonators. The proposed scheme not only requires a relative low lasing threshold, but also exhibits extremely broad tunability extending from ...
Johnson, T. J., Lin, Q., Michael, C. P., Painter, O. J., Perahia, R.   +4 more
core   +1 more source

Three Methods of Fetal Weight Estimation Compared in Women With BMI ≥ 35 kg/m2 at Term—A Prospective Observational Study

Birth, EarlyView.
Visual summary of a prospective study comparing sonographic, maternal, and clinical fetal‐weight estimation methods in women with BMI = 35 kg/m2 at term. The graphical abstract presents the study objective, design, accuracy measures, and the primary finding that maternal and sonographic estimations demonstrated similar accuracy and both exceeded that ...
Inshirah Sgayer, Yara N. Francis, Nadine Ashkar‐Majadla, Ruba Tuma, Lior Lowenstein, Maya Frank Wolf, Marwan Odeh   +6 more
wiley   +1 more source

Time-resolved Spectral Analysis Of Phase Conjugation By Four-wave Mixing In Semiconductor Optical Amplifiers [PDF]

, 1997
Optical phase conjugation provides a mechanism for achieving dispersion compensation in optical fibers. This has been demonstrated by four-wave mixing (FWM) in both fiber and semiconductor optical amplifiers (SOAs).
Geraghty, David F., Lee, Robert B., Mathur, Atul, Vahala, Kerry J., Verdiell, Marc, Ziari, Mehrdad   +5 more
core