Terahertz near-field imaging of dielectric resonators.

As an alternative to metallic resonators, dielectric resonators can increase radiation efficiencies of metasurfaces at terahertz frequencies. Such subwavelength resonators made from low-loss dielectric materials operate on the basis of oscillating displacement currents. For full control of electromagnetic waves, it is essential that dielectric resonators operate around their resonant modes. Thus, understanding the nature of these resonances is crucial towards design implementation. To this end, an array of silicon resonators on a quartz substrate is designed to operate in transmission at terahertz frequencies. The resonator dimensions are tailored to observe their low-order modes of resonance at 0.58 THz and 0.61 THz respectively. We employ a terahertz near-field imaging technique to measure the complex near-fields of this dielectric resonator array. This unique method allows direct experimental observation of the first two fundamental resonances.

[1]  Andreas Bitzer,et al.  Terahertz near-field imaging of metallic subwavelength holes and hole arrays , 2008 .

[2]  W. Withayachumnankul,et al.  Mechanically Tunable Dielectric Resonator Metasurfaces at Visible Frequencies. , 2016, ACS nano.

[3]  Derek Abbott,et al.  Ultrabroadband reflective polarization convertor for terahertz waves , 2014 .

[4]  A. Bitzer,et al.  Near-field signature of electromagnetic coupling in metamaterial arrays: a terahertz microscopy study. , 2011, Optics express.

[5]  D. Grischkowsky,et al.  Far-infrared time-domain spectroscopy with terahertz beams of dielectrics and semiconductors , 1990 .

[6]  Igal Brener,et al.  Polarization-Independent Silicon Metadevices for Efficient Optical Wavefront Control. , 2015, Nano letters.

[7]  Derek Abbott,et al.  Polarization-dependent thin-film wire-grid reflectarray for terahertz waves , 2015 .

[8]  M. R. Chaharmir,et al.  A Wideband Transmitarray Using Dual-Resonant Double Square Rings , 2010, IEEE Transactions on Antennas and Propagation.

[9]  Thomas Feurer,et al.  Terahertz near-field microscopy of complementary planar metamaterials: Babinet's principle. , 2011, Optics express.

[10]  Kebin Fan,et al.  Experimental realization of a terahertz all-dielectric metasurface absorber. , 2017, Optics express.

[11]  Ajay Nahata,et al.  Electric field vector characterization of terahertz surface plasmons. , 2007, Optics express.

[12]  Derek Abbott,et al.  Terahertz Magnetic Mirror Realized with Dielectric Resonator Antennas , 2015, Advanced materials.

[13]  A Doi,et al.  Real-time terahertz near-field microscope. , 2011, Optics express.

[14]  Yandong Gong,et al.  An ultrathin terahertz quarter-wave plate using planar babinet-inverted metasurface. , 2015, Optics express.

[15]  Siqi Yan,et al.  Generation of Terahertz Vortices Using Metasurface With Circular Slits , 2014, IEEE Photonics Journal.

[16]  Derek Abbott,et al.  Sub-diffraction thin-film sensing with planar terahertz metamaterials. , 2011, Optics express.

[17]  Tao Chen,et al.  Metamaterials Application in Sensing , 2012, Sensors.

[18]  D. Grischkowsky,et al.  Terahertz time-domain spectroscopy characterization of the far-infrared absorption and index of refraction of high-resistivity, float-zone silicon , 2004 .

[19]  Arnan Mitchell,et al.  Dielectric resonator nanoantennas at visible frequencies. , 2013, Optics express.

[20]  Derek Abbott,et al.  Dielectric Resonator Reflectarray as High-Efficiency Nonuniform Terahertz Metasurface , 2016 .

[21]  Anthony Grbic,et al.  Efficient light bending with isotropic metamaterial Huygens' surfaces. , 2014, Nano letters.

[22]  Aurèle J. L. Adam,et al.  Review of Near-Field Terahertz Measurement Methods and Their Applications , 2011 .

[23]  N. Zheludev,et al.  From metamaterials to metadevices. , 2012, Nature materials.

[24]  Igal Brener,et al.  Active tuning of all-dielectric metasurfaces. , 2015, ACS nano.

[25]  C. Pfeiffer,et al.  Cascaded metasurfaces for complete phase and polarization control , 2013 .

[26]  Derek Abbott,et al.  Second-Order Terahertz Bandpass Frequency Selective Surface With Miniaturized Elements , 2015, IEEE Transactions on Terahertz Science and Technology.

[27]  Christophe Fumeaux,et al.  Reflectarray antennas for terahertz communications , 2012 .

[28]  Lei Wang,et al.  Efficient Polarization-Insensitive Complex Wavefront Control Using Huygens’ Metasurfaces Based on Dielectric Resonant Meta-atoms , 2016, 1602.00755.

[29]  S. Maier,et al.  Terahertz All-Dielectric Magnetic Mirror Metasurfaces , 2016 .

[30]  Derek Abbott,et al.  Terahertz reflectarray as a polarizing beam splitter. , 2014, Optics express.

[31]  P. Kužel,et al.  Near-field probing of Mie resonances in single TiO2 microspheres at terahertz frequencies. , 2014, Optics express.

[32]  Arnan Mitchell,et al.  Efficiency and Scalability of Dielectric Resonator Antennas at Optical Frequencies , 2014, IEEE Photonics Journal.

[33]  Andreas Bitzer,et al.  Terahertz near-field microscopy with subwavelength spatial resolution based on photoconductive antennas. , 2010, Applied optics.

[34]  I. Al-Naib,et al.  Ultrasensitive terahertz sensing with high-Q Fano resonances in metasurfaces , 2014, 1406.7194.

[35]  I. Brener,et al.  Tailoring directional scattering through magnetic and electric resonances in subwavelength silicon nanodisks. , 2013, ACS nano.

[36]  Polarization-independent and high-efficiency dielectric metasurfaces for visible light. , 2015, Optics express.

[37]  Jeremy B. Wright,et al.  Optical magnetic mirrors without metals , 2014, 1403.1308.

[38]  M. Nagel,et al.  Terahertz near-field vectorial imaging of subwavelength apertures and aperture arrays. , 2009, Optics express.

[39]  Hanspeter Helm,et al.  Terahertz near-field imaging of electric and magnetic resonances of a planar metamaterial. , 2009, Optics express.

[40]  Q. Wei,et al.  Generation of steep phase anisotropy with zero-backscattering by arrays of coupled dielectric nano-resonators , 2014 .

[41]  Christophe Fumeaux,et al.  Experimental demonstration of reflectarray antennas at terahertz frequencies. , 2012, Optics express.

[42]  Christian Debus,et al.  Frequency selective surfaces for high sensitivity terahertz sensing , 2007, 2104.05462.

[43]  N. Yu,et al.  Light Propagation with Phase Discontinuities: Generalized Laws of Reflection and Refraction , 2011, Science.