Search Constraints

Start Over
Filtering by: Alternative title ssim FS 58 Remove constraint Alternative title ssim: FS 58 Academic Affiliation Physics Remove constraint Academic Affiliation: Physics

Search Results

  • High-field terahertz response of graphene

    Creator:
    Paul, M. J., Chang, Y. C., Thompson, Z. J., Stickel, A., Wardini, J., Choi, H., Minot, E. D., Norris, T. B., and Lee, Yun-Shik
    Abstract:
    We investigate the response of multi-layer epitaxial graphene and chemical vapor deposition (CVD)-grown single-layer graphene to strong terahertz (THz) fields. Contrary to theoretical predictions of strong nonlinear response, the transmitted fields exhibit no harmonic generation, indicating that the nonlinear response is limited by fast electron thermalization due to carrier-carrier scattering....
    Resource Type:
    Article
    Full Text:
    system (lambda cubed laser system at University of Michigan) produces 30 fs, 3mJ pulses [35]. The beam is

  • Study of Organic Semiconductors Using Time-Resolved Charge Measurements at the Microscale

    Creator:
    Wallace, Richard
    Abstract:
    Understanding charge transfer in organic semiconductors is important for developing devices like organic light emitting diodes and flexible electronics. Optical tweezers have been used in many disciplines for trapping, manipulating, and analyzing microscopic objects such as microspheres, micro-organisms, and other colloidal particles. Using optical tweezers, studies have measured the average...
    Resource Type:
    Undergraduate Thesis
    Full Text:
    -spring system and can be described using Hooke’s Law. (See figure 2.1) Fs = −ks~r Here ks is the force

  • Optical Tweezer Trapping of Colloidal Polystyrene and Silica Microspheres

    Creator:
    Peters, Kyle C.
    Abstract:
    Optical trapping is a tool used throughout a wide variety of disciplines rang- ing from precisely probing and manipulating sub-micron organisms in biol- ogy to analyzing fundamental charge transfer in colloidal physics. This thesis presents research involving optical tweezer force measurements of polystyrene and silica microspheres. In addition, preliminary work...
    Resource Type:
    Undergraduate Thesis
    Full Text:
    = � Z Fs(x) dx = 1 2 ktrapx(t) 2 1 2 ktrapx(t) 2 = ax(t)2 (4.8) Eqn. (4.8) states that it is

  • Nonlinear Terahertz Spectroscopy and imaging of Carbon Nanomaterials

    Creator:
    Lee, Byounghwak
    Abstract:
    This dissertation presents nonlinear terahertz (THz) properties of carbon nanomaterials investigated by time-resolved high-field THz spectroscopy. In order to determine THz characteristics of nanomaterials, we performed THz power spectrum measurement, THz raster imaging, THz time-domain spectroscopy (THz-TDS) and time-resolved pump-probe experiment on two different types of single layer graphene and...
    Resource Type:
    Dissertation
    Full Text:
    laser pulses (pulse energy, 1 mJ; pulse duration, 100 fs; repetition rate, 1 kHz) with titled pulse

  • Optical Development and Materials Applications of Tunable Femtosecond Stimulated Raman Spectroscopy

    Creator:
    Zhu, Liangdong
    Abstract:
    To obtain a mechanistic understanding of the chemical processes, techniques that offer a frame-by-frame visualization of molecular structure during a reaction are of vital importance. Numerous efforts and advances have been made in order to acquire such vivid molecular “movies”, especially in the electronic excited state. Ultrafast molecular spectroscopy method...
    Resource Type:
    Dissertation
    Full Text:
    Figure 2.3 Scheme of a fs noncollinear OPA in the visible region. .................................. 22

  • De-Haas van-Alphen effect in the quantum limit

    Creator:
    Karniewicz, Joseph J.
    Abstract:
    In this work we apply the finite temperature formulation of quantum statistical mechanics to an analysis of the de Haas-van Alphen effect in the quantum limit. A new expression is derived for the differential magnetic susceptibility which clearly shows the individual contributions of zero-temperature and non-zero temperature terms. Interactions have...
    Resource Type:
    Dissertation
    Full Text:
    d =1.2 N=3 T=.3 T d =.1 N=3 47 48 49 50 51 52 53 51 55 56 57 58 59 60 61 62 63 61 65

  • Generation and manipulation of THz waves

    Creator:
    Amer, Naaman
    Abstract:
    In this thesis I studied several THz components that can be used for potential THz technology. THz waves were generated in nonlinear medium via optical rectification of femtosecond optical pulses. Utilizing the phase matching condition between the optical and THz waves in a ZnTe crystal, single-cycle broad-band THz pulses were...
    Resource Type:
    Dissertation
    Full Text:
    ...................................................................................................................58 3.4 Adaptive THz pulse shaping in a fanned-out PPLN

  • Nonlinear Photocarrier Dynamics in Multilayer WSe2 Induced by Intense Terahertz Pulses

    Creator:
    Guay, Viela, Johnson, Nathan, Zhang, Yue, Van Der Zande, Arend M., Thorp, Spencer G., Graham, Matthew, and Lee, Yun-Shik
    Abstract:
    Non-equilibrium photocarriers in multilayer WSe2 injected by femtosecond laser pulses exhibit extraordinary nonlinear dynamics in the presence of intense THz fields. The THz absorption in optically excited WSe2 rises rapidly in the low THz field regime and gradually ramp up at high intensities. The strong THz pulses drive the photocarriers...
    Resource Type:
    Article
    Full Text:
    amplifier (wavelength, 800 nm;57 pulse energy, 1 mJ; pulse duration, 100 fs) [38,40]. THz pulses are focused

  • Generation of narrowband THz pulses and THz studies of ultrafast phenomena in semiconductor quantum wells

    Creator:
    Danielson, Jeremy R.
    Abstract:
    This work comprises two main parts: creating and shaping narrowband, pulsed THz radiation in a table-top optical setup; and applying THz pulses to semiconductor nanostructures to study electron dynamics. I developed a scheme to shape the THz output of a fanned-out periodically poled lithium niobate (PPLN) crystal. The pulses are...
    Resource Type:
    Dissertation
    Full Text:
    ............................................................ 58 4.1 Quantum Well Potential................................................................... 60

  • Generation of terahertz pulses with arbitrary elliptical polarization

    Creator:
    Amer, N., Hurlbut, Walter C., Norton, B. J., Lee, Yun-Shik, and Norris, T. B.
    Abstract:
    We employ two different methods to generate controllable elliptical polarization of teraherz (THz) pulses. First, THz pulses are generated via optical rectification in nonlinear crystals using a pair of temporally separated and perpendicularly polarized optical pulses. The THz ellipticity is controlled by adjusting the relative time delay and polarization of...
    Resource Type:
    Article
    Full Text:
    � producing 820 nm, 85 fs pulses. The femtosecond pulses were focused to a spot of 20 �m diameter in the