Plasmonic waveguide with folded stubs for highly confined terahertz propagation and concentration.

We proposed a novel planar terahertz (THz) plasmonic waveguide with folded stub arrays to achieve excellent terahertz propagation performance with tight field confinement and compact size based on the concept of spoof surface plasmon polaritons (spoof SPPs). It is found that the waveguide propagation characteristics can be directly manipulated by increasing the length of the folded stubs without increasing its lateral dimension, which exhibits much lower asymptotic frequency of the dispersion relation and even tighter terahertz field confinement than conventional plasmonic waveguides with rectangular stub arrays. Based on this waveguiding scheme, a terahertz concentrator with gradual step-length folded stubs is proposed to achieve high terahertz field enhancement, and an enhancement factor greater than 20 is demonstrated. This work offers a new perspective on very confined terahertz propagation and concentration, which may have promising potential applications in various integrated terahertz plasmonic circuits and devices, terahertz sensing and terahertz nonlinear optics.

[1]  Qiang Cheng,et al.  Broadband and high‐efficiency conversion from guided waves to spoof surface plasmon polaritons , 2014 .

[2]  E. Ozbay.  Plasmonics: Merging Photonics and Electronics at Nanoscale Dimensions , 2006, Science.

[3]  Tie Jun Cui,et al.  Planar plasmonic metamaterial on a thin film with nearly zero thickness , 2013 .

[4]  P. Crozat,et al.  THz surface plasmon modes on planar Goubau lines. , 2012, Optics express.

[5]  Qing Huo Liu,et al.  Strongly Confined Spoof Surface Plasmon Polaritons Waveguiding Enabled by Planar Staggered Plasmonic Waveguides , 2016, Scientific Reports.

[6]  Yong Jin Zhou,et al.  Planar spoof plasmonic ultra-wideband filter based on low-loss and compact terahertz waveguide corrugated with dumbbell grooves. , 2015, Applied optics.

[7]  Mark L. Brongersma,et al.  Plasmonics: the next chip-scale technology , 2006 .

[8]  Tie Jun Cui,et al.  Conformal surface plasmons propagating on ultrathin and flexible films , 2012, Proceedings of the National Academy of Sciences.

[9]  Stefan A Maier,et al.  Terahertz surface plasmon-polariton propagation and focusing on periodically corrugated metal wires. , 2006, Physical review letters.

[10]  S. R. Andrews,et al.  Highly confined guiding of terahertz surface plasmon polaritons on structured metal surfaces , 2008 .

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

[12]  D. Gramotnev,et al.  Plasmonics beyond the diffraction limit , 2010 .

[13]  Gu Ben,et al.  Surface plasmon subwavelength optics:principles and novel effects , 2007 .

[14]  E. Kriezis,et al.  Surface plasmon circuitry in opto-electronics , 2012, 2012 Conference on Lasers and Electro-Optics (CLEO).

[15]  Shuncong Zhong,et al.  High-mode spoof SPP of periodic metal grooves for ultra-sensitive terahertz sensing. , 2014, Optics express.

[16]  Zhanghua Han,et al.  Spoof surface plasmon-based stripe antennas with extreme field enhancement in the terahertz regime. , 2015, Optics letters.

[17]  R. Leonhardt,et al.  Terahertz pulse propagation in 3D-printed waveguide with metal wires component. , 2014, Optics express.

[18]  J. Pendry,et al.  Mimicking Surface Plasmons with Structured Surfaces , 2004, Science.

[19]  Ajay Nahata,et al.  Plasmonic waveguides based on symmetric and asymmetric T-shaped structures. , 2014, Optics express.

[20]  X-C Zhang,et al.  Terahertz field enhancement to the MV/cm regime in a tapered parallel plate waveguide. , 2012, Optics express.

[21]  Moon-Ho Jo,et al.  Near-field electrical detection of optical plasmons and single plasmon sources , 2009, Proceedings of the Fourth European Conference on Antennas and Propagation.

[22]  Zhanghua Han,et al.  Radiation guiding with surface plasmon polaritons , 2013, Reports on progress in physics. Physical Society.

[23]  Esteban Moreno,et al.  Terahertz wedge plasmon polaritons. , 2009, Optics letters.

[24]  S. Kawata,et al.  Plasmonics for near-field nano-imaging and superlensing , 2009 .

[25]  Tie Jun Cui,et al.  Broadband amplification of spoof surface plasmon polaritons at microwave frequencies , 2015 .

[26]  P. Mazumder,et al.  Dynamic Terahertz Spoof Surface Plasmon–Polariton Switch Based on Resonance and Absorption , 2011, IEEE Transactions on Electron Devices.