Polymer stabilized liquid crystal phase shifter for terahertz waves.

We propose an electrically tunable phase shifter for terahertz frequencies. The device is based on a polymer stabilized liquid crystal which allows for a simple device geometry. The polymer stabilized liquid crystal enables continuous tuning of the introduced phase shift with only one pair of electrodes. By characterizing the device with terahertz time-domain spectroscopy we demonstrate a phase shift up to 2.5 terahertz, only slightly changed properties of the neat liquid crystal and significantly reduced response times.

[1]  T. Faber,et al.  The Frank constants of nematic 5CB at atmospheric pressure , 1981 .

[2]  I. Dierking.  Recent developments in polymer stabilised liquid crystals , 2010 .

[3]  Ingo Dierking,et al.  Polymer Network–Stabilized Liquid Crystals , 2000 .

[4]  M. Koch,et al.  Analyzing sub-100-μm samples with transmission terahertz time domain spectroscopy , 2009 .

[5]  Daniel M. Mittleman,et al.  Metal wires for terahertz wave guiding , 2004, Nature.

[6]  N. Vieweg,et al.  Electrically Tunable Terahertz Notch Filters , 2012 .

[7]  R. Jacobsen,et al.  Generation and detection of terahertz pulses from biased semiconductor antennas , 1996 .

[8]  R. Wilk,et al.  Highly Accurate THz Time-Domain Spectroscopy of Multilayer Structures , 2008, IEEE Journal of Selected Topics in Quantum Electronics.

[9]  Willie J Padilla,et al.  A metamaterial solid-state terahertz phase modulator , 2009 .

[10]  Martin Koch,et al.  THz Properties of Nematic Liquid Crystals , 2010 .

[11]  E. Cebe,et al.  Rotational viscosity in liquid crystals: A molecular dynamics study , 2005 .

[12]  N. Vieweg,et al.  Terahertz properties of liquid crystals with negative dielectric anisotropy. , 2010, Applied optics.

[13]  Ci-Ling Pan,et al.  The complex refractive indices of the liquid crystal mixture E7 in the terahertz frequency range , 2010 .

[14]  V. Shalaev.  Optical negative-index metamaterials , 2007 .

[15]  R. Dąbrowski,et al.  Liquid crystal phase shifters at millimeter wave frequencies , 2012 .