Tunable optical and magneto-optical properties of ferrofluid in the terahertz regime.

The dielectric property and magneto-optical effects of ferrofluids have been investigated in the terahertz (THz) regime by using THz time-domain spectroscopy. The experiment results show that the refractive index and absorption coefficient of ferrofluid for THz waves rise up with the increase of nanoparticle concentration in the ferrofluid. Moreover, two different THz magneto-optical effects have been found with different external magnetic fields, of which mechanisms have been theoretically explained well by microscopic structure induced refractive index change in the magnetization process and the transverse magneto-optical effect after the saturation magnetization, respectively. This work suggests that ferrofluid is a promising magneto-optical material in the THz regime which has widely potential applications in THz functional devices for THz sensing, modulation, phase retardation, and polarization control.

[1]  Yingli Liu,et al.  Terahertz metamaterials with VO2 cut-wires for thermal tunability , 2010 .

[2]  Ci-Ling Pan,et al.  Magnetically tunable room-temperature 2 pi liquid crystal terahertz phase shifter. , 2004, Optics express.

[3]  Ci-Ling Pan,et al.  Voltage-controlled liquid-crystal terahertz phase shifter and quarter-wave plate. , 2006, Optics letters.

[4]  Sai Chen,et al.  State conversion based on terahertz plasmonics with vanadium dioxide coating controlled by optical pumping. , 2013, Optics letters.

[5]  Hui Zhang,et al.  Liquid-crystal-filled photonic crystal for terahertz switch and filter , 2009 .

[6]  Shieh-Yueh Yang,et al.  Origin and applications of magnetically tunable refractive index of magnetic fluid films , 2004 .

[7]  H. Kurz,et al.  Transmission of THz radiation through InSb gratings of subwavelength apertures. , 2005, Optics express.

[8]  L. Molenkamp,et al.  Giant magneto-optical faraday effect in HgTe thin films in the terahertz spectral range. , 2011, Physical review letters.

[9]  Zhen Tian,et al.  A perfect metamaterial polarization rotator , 2013 .

[10]  I Gaponenko,et al.  Intrinsic terahertz plasmons and magnetoplasmons in large scale monolayer graphene. , 2012, Nano letters.

[11]  G. Plopper,et al.  Sensing minute changes in biological cell monolayers with THz differential time-domain spectroscopy. , 2007, Biosensors & bioelectronics.

[12]  S. Maier,et al.  Active control of electromagnetically induced transparency analogue in terahertz metamaterials , 2012, Nature Communications.

[13]  Hanspeter Helm,et al.  Metal-insulator phase transition in a VO2 thin film observed with terahertz spectroscopy , 2006 .

[14]  R. Morandotti,et al.  Terahertz Faraday rotation in a magnetic liquid: High magneto-optical figure of merit and broadba , 2012 .

[15]  I. A. Ibraheem,et al.  Low-Dispersive Dielectric Mirrors for Future Wireless Terahertz Communication Systems , 2008, IEEE Microwave and Wireless Components Letters.

[16]  Sai Chen,et al.  Tunable nonreciprocal terahertz transmission and enhancement based on metal/magneto-optic plasmonic lens. , 2013, Optics express.

[17]  G. Armelles,et al.  Magnetoplasmonics: Combining Magnetic and Plasmonic Functionalities , 2013 .

[18]  Richard G. Baraniuk,et al.  Terahertz imaging with compressed sensing and phase retrieval , 2008 .

[19]  Yan-ge Liu,et al.  Fiber-optic in-line magnetic field sensor based on the magnetic fluid and multimode interference effects , 2013 .

[20]  Xianfeng Chen,et al.  Magnetic-field-induced birefringence and particle agglomeration in magnetic fluids , 2006 .

[21]  Bo Liu,et al.  Magnetically tunable terahertz magnetoplasmons in ferrofluid-filled photonic crystals , 2013 .

[22]  Ming Ding,et al.  A compact broadband microfiber Bragg grating. , 2011, Optics express.

[23]  Tiegen Liu,et al.  Optical fiber magnetic field sensor based on single-mode-multimode-single-mode structure and magnetic fluid. , 2013, Optics letters.

[24]  Shengjiang Chang,et al.  Real-time quantitative terahertz microfluidic sensing based on photonic crystal pillar array , 2013 .

[25]  Willie J Padilla,et al.  Active terahertz metamaterial devices , 2006, Nature.

[26]  R. Morandotti,et al.  A magnetic non-reciprocal isolator for broadband terahertz operation , 2013, Nature Communications.