Polarization Enhancement of Terahertz Radiation Generated by Intrinsic Josephson Junctions in a Truncated Edge Square Bi2Sr2CaCu2O8+δ Mesa

Elarabi, Asem; Yoshioka, Yusuke; Tsujimoto, Manabu; Nakagawa, Yasuyoshi; Kakeya, Itsuhiro

doi:10.1016/j.phpro.2016.04.022

Cited by 5 publications

(9 citation statements)

References 11 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The initial design parameters were determined using the commercial full-wave three-dimensional finiteelement electromagnetic simulation software-Ansys HFSS [26]. Similar simplified methods have previously been used to determine cavity resonance conditions [26,38], and a more advanced method, capable of solving sine-Gordon equations, was used to determine polarization properties [25]. A model similar to that reported in [26] was used, wherein the dielectric constant 𝜖 = 17.6, and the feeding point is placed over the horizontal axis of the geometry.…”

Section: B Electromagnetic Simulationmentioning

confidence: 99%

“…Similar simplified methods have previously been used to determine cavity resonance conditions [26,38], and a more advanced method, capable of solving sine-Gordon equations, was used to determine polarization properties [25]. A model similar to that reported in [26] was used, wherein the dielectric constant 𝜖 = 17.6, and the feeding point is placed over the horizontal axis of the geometry. To account for the losses incurred owing to the skin effect, an impedance boundary condition was applied to the model [39], and the complex surface impedance was estimated by using, both, the Zimmermann method [26,39,40] and the a-b surface resistance correction [41] given by…”

Section: B Electromagnetic Simulationmentioning

confidence: 99%

“…A model similar to that reported in [26] was used, wherein the dielectric constant 𝜖 = 17.6, and the feeding point is placed over the horizontal axis of the geometry. To account for the losses incurred owing to the skin effect, an impedance boundary condition was applied to the model [39], and the complex surface impedance was estimated by using, both, the Zimmermann method [26,39,40] and the a-b surface resistance correction [41] given by…”

Section: B Electromagnetic Simulationmentioning

confidence: 99%

“…Waves emitted from rectangular IJJ-based sources have been known to be linearly polarized [2]. However, recent numerical studies [14,25,26] have proposed the possibility of realizing circularly polarized emissions from IJJ devices. This paper reports the first experimental demonstration of the generation of circularly polarized sub-THz waves from a monolithic source-a superconducting IJJ stack-wherein the ellipticity and evolution direction are tuned by mesa shape and bias conditions.…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Monolithic Superconducting Emitter of Tunable Circularly Polarized Terahertz Radiation

et al. 2017

Self Cite

View full text Add to dashboard Cite

We propose an approach to control the polarization of terahertz (THz) radiation from intrinsic Josephsonjunction stacks in single crystalline high-temperature superconductor Bi2Sr2CaCu2O8. Monolithic control of the surface high-frequency current distributions in the truncated square mesa structure allows us to modulate the polarization of the emitted THz wave as a result of two orthogonal fundamental modes excited inside the mesa. Highly polarized circular terahertz waves with a degree of circular polarization of more than 99% can be generated using an electrically controlled method. The intuitive results obtained from the numerical simulation based on the conventional antenna theory are consistent with the observed emission characteristics.

show abstract

Section: B Electromagnetic Simulationmentioning

confidence: 99%

Section: B Electromagnetic Simulationmentioning

confidence: 99%

Section: B Electromagnetic Simulationmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Monolithic Superconducting Emitter of Tunable Circularly Polarized Terahertz Radiation

et al. 2017

Self Cite

View full text Add to dashboard Cite

show abstract

“…Furthermore, we revealed that the ellipticity and handedness of the THz waves change dramatically with the heating position. Recently, emissions of circularly polarized THz wave were experimentally reported from a truncated-edge square mesa [30], and their characteristics were investigated with a simple antenna analysis [31]. In the truncated-edge mesa, the cavity modes along two diagonal lines of the mesa will become eigenmodes.…”

mentioning

confidence: 99%

Control of circularly polarized THz wave from intrinsic Josephson junctions by local heating

Asai

Kawabata

2017

Applied Physics Letters

View full text Add to dashboard Cite

This paper reports a practical method of generating circularly polarized terahertz (THz) waves from intrinsic Josephson junctions (IJJs) and controlling their polarization states by external local heating. We theoretically find that a mesa-structure IJJ whose geometry is almost square can emit circularly polarized THz waves by local heating of the mesa. Moreover, we demonstrate that the polarization states of the THz waves change dramatically with the local heating position. Our results indicate that the use of local heating can provide a high level of controllability of the THz emissions and significantly extend the range of applications of IJJ-based THz emitters.Terahertz (THz) electromagnetic (EM) waves have potential applications in a wide range of fields, e.g. nondestructive inspection of materials, medical diagnosis, bio-sensing, and high-speed wireless communication [1]. Toward the realization of a practical THz emitter, various THz sources, such as quantum-cascade lasers and resonant-tunneling diodes, have been studied so far [2,3]. Since the first observation of intense and continuous THz wave emitted from a Bi 2 Sr 2 CaCu 2 O 8+δ (Bi2212) single crystal by Ozyuzer et al. [4], considerable attention has been paid to high-T c cuprate superconductors. A layered structure of Bi2212 single crystals composed of superconducting layers and insulating layers forms a stack of the Josephson junctions whose thicknesses are on the atomic scale ∼ 1.5 nm. Stacks of these natural Josephson junctions, which are referred to as intrinsic Josephson junctions (IJJs), can generate an AC Josephson current in the THz frequency range by application of a voltage, and the THz wave emission is attributed to the generation of this current. Intense THz emissions have been reported for IJJs fabricated in a mesa geometry, which itself behaves as a cavity resonator, and thus, a number of studies on such IJJ mesas have been carried out both experimentally [4][5][6][7][8][9][10][11][12][13][14][15] and theoretically [16][17][18][19][20][21][22][23][24][25][26]. However, in the previous studies, little attention was given to the state of the polarization of the THz waves. Control of the polarization is a fundamental issue for technological applications of THz waves. In particular, the ability to generate and control circularly polarized THz waves would open the way to various applications such as circular dichroism of proteins [27].In this paper, we present a method of generating and controlling circularly polarized THz waves from IJJ mesas by using external local heating. We consider a IJJ mesa whose geometry is almost square and whose temperature distribution is controlled by laser heating (see Fig. 1). We numerically investigate the emission power and the polarization of the THz waves from the mesa by solving the sine-Gordon and the Maxwell equations simultaneously. Interestingly, both the ellipticity and handedness of the THz waves from the IJJ mesa strongly depend on the position of the laser heating. Figure 1 shows a schematic fig...

show abstract

Circularly polarized terahertz radiation monolithically generated by cylindrical mesas of intrinsic Josephson junctions

Elarabi

Yoshioka

Tsujimoto

et al. 2018

Applied Physics Letters

View full text Add to dashboard Cite

We report emissions of circular polarized electromagnetic waves from cylindrically shaped mesa structures of the high-temperature superconductor Bi2Sr2CaCu2O8+δ. The frequency range of circularly polarized emission of a cylindrical mesa with notched sides is between 400 and 430 GHz, which is wider than expected by the patch antenna theory. Three maxima recognized in emission intensity are presumably attributed to excitations of fundamental orthogonal modes and circularly polarized modes. Along with the demonstration of circularly polarized emission from truncated edge square mesas, the obtained results provide a wide variety of engineering designs of compact and solid-state electromagnetic sources which are able to generate circularly-polarized terahertz waves.

show abstract

Polarization Enhancement of Terahertz Radiation Generated by Intrinsic Josephson Junctions in a Truncated Edge Square Bi2Sr2CaCu2O8+δ Mesa

Cited by 5 publications

References 11 publications

Monolithic Superconducting Emitter of Tunable Circularly Polarized Terahertz Radiation

Monolithic Superconducting Emitter of Tunable Circularly Polarized Terahertz Radiation

Control of circularly polarized THz wave from intrinsic Josephson junctions by local heating

Circularly polarized terahertz radiation monolithically generated by cylindrical mesas of intrinsic Josephson junctions

Contact Info

Product

Resources

About