Researching | Singleshot terahertz polarization detection based on terahertz timedomain spectroscopy

Journals >Photonics Research >Volume 10 >Issue 6 >Page 1374 > Article

Photonics Research
Vol. 10, Issue 6, 1374 (2022)

Single-shot terahertz polarization detection based on terahertz time-domain spectroscopy

Qinggang Lin^1、2, Xinming Yuan¹, Xuanke Zeng^1、3, Yatao Yang², Yi Cai¹, Xiaowei Lu¹, Maijie Zheng¹, Congying Wang¹, Wenhua Cao², and Shixiang Xu^1、*

Author Affiliations

¹Shenzhen Key Laboratory of Micro-Nano Photonic Information Technology, Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen 518060, China

²College of Electronics and Information Engineering, Shenzhen University, Shenzhen 518060, China

³e-mail: xuankezeng@szu.edu.cn

show less

DOI: 10.1364/PRJ.449196 Cite this Article Set citation alerts

Qinggang Lin, Xinming Yuan, Xuanke Zeng, Yatao Yang, Yi Cai, Xiaowei Lu, Maijie Zheng, Congying Wang, Wenhua Cao, Shixiang Xu. Single-shot terahertz polarization detection based on terahertz time-domain spectroscopy[J]. Photonics Research, 2022, 10(6): 1374 Copy Citation Text

show less

Abstract

This paper presents a novel design for single-shot terahertz polarization detection based on terahertz time-domain spectroscopy (THz-TDS). Its validity has been confirmed by comparing its detection results with those of the THz common-path spectral interferometer through two separate measurements for the orthogonal components. Our results also show that its detection signal-to-noise ratios (SNRs) are obviously superior to those of the 45° optical bias THz-TDS by electro-optical sampling due to its operation on common-path spectral interference rather than the polarization-sensitive intensity modulation. The setup works without need of any optical scan, which does not only save time, but also efficiently avoids the disturbances from the fluctuations of the system and environment. Its single-shot mode allows it to work well for the applications with poor or no repeatability.

I_{s} = \frac{I_{p} ω n^{3} γ_{41} E_{THz} L}{2 c} [2 \sin α \cdot \cos (4 φ) + \cos α \cdot \sin (4 φ)] .

(1)

View in Article

I_{s, 1} = \frac{I_{p} ω n^{3} γ_{41} L}{c} E_{THz} \sin α,

(2)

View in Article

I_{s, 2} = \frac{I_{p} ω n^{3} γ_{41} L}{2 c} E_{THz} \cos α,

(3)

View in Article

(\begin{matrix} E_{x} \\ E_{y} \end{matrix}) = \frac{\sqrt{2}}{2} (\begin{matrix} \cos θ & - \sin θ \\ \sin θ & \cos θ \end{matrix}) (\begin{matrix} \exp (- i \frac{φ}{2}) & 0 \\ 0 & \exp (i \frac{φ}{2}) \end{matrix}) \cdot (\begin{matrix} \cos θ & \sin θ \\ - \sin θ & \cos θ \end{matrix}) (\begin{matrix} 1 & i \\ i & 1 \end{matrix}) (\begin{matrix} E_{p} \\ 0 \end{matrix}) = \frac{\sqrt{2}}{2} E_{p} (\begin{matrix} \cos (\frac{φ}{2}) - i \exp (i 2 θ) \cdot \sin (\frac{φ}{2}) \\ i \cos (\frac{φ}{2}) - \exp (i 2 θ) \cdot \sin (\frac{φ}{2}) \end{matrix}) .

(4)

View in Article

φ \approx \frac{ω n^{3} E_{THz} γ_{41} L}{2 c} [2 \sin α \cdot \sin (2 θ) - \cos α \cdot \cos (2 θ)] .

(5)

View in Article

(\begin{matrix} S_{0} \\ S_{1} \\ S_{2} \\ S_{3} \end{matrix}) = (\begin{matrix} I_{p} \\ \frac{I_{p} ω n^{3} γ_{41} L}{c} E_{THz} \sin α \\ \frac{I_{p} ω n^{3} γ_{41} L}{2 c} E_{THz} \cos α \\ - I_{p} \cos φ \end{matrix}),

(6)

View in Article

(\begin{matrix} E_{p x} \\ E_{p y} \end{matrix}) = (\begin{matrix} 0 & 0 \\ 0 & 1 \end{matrix}) (\begin{matrix} \cos 45^{o} & - \sin 45^{o} \\ \sin 45^{o} & \cos 45^{o} \end{matrix}) (\begin{matrix} \exp (- i \frac{β (λ)}{2}) & 0 \\ 0 & \exp (i \frac{β (λ)}{2}) \end{matrix}) (\begin{matrix} \cos 45^{o} & \sin 45^{o} \\ - \sin 45^{o} & \cos 45^{o} \end{matrix}) (\begin{matrix} 1 & 0 \\ 0 & i \end{matrix}) (\begin{matrix} E_{x} \\ E_{y} \end{matrix}) = i (\begin{matrix} 0 \\ E_{y} \cos (\frac{β (λ)}{2}) - E_{x} \sin (\frac{β (λ)}{2}) \end{matrix}) .

(7)

View in Article

P (λ) = {| E_{p x} |}^{2} + {| E_{p y} |}^{2} = \frac{1}{2} S_{0} (λ) - \frac{1}{4} [S_{1} (λ) - i \cdot S_{2} (λ)] \exp [i β (λ)] - \frac{1}{4} [S_{1} (λ) + i \cdot S_{2} (λ)] \exp [- i β (λ)] = \frac{1}{2} S_{0} (λ) - \frac{1}{2} | S_{12} (λ) | \cdot \cos [β (λ) + σ (λ)],

(8)

View in Article

Φ (λ) = [β (λ_{0}) + 2 π L λ_{0}] + Λ (λ),

(9a)

View in Article

L = d \frac{{Δ n_{g} |}_{λ = λ_{0}}}{λ_{0}^{2}} .

(9b)

View in Article

φ_{THz, ∥} (ω) \to φ_{THz, ∥} (λ) = \frac{- 1}{F_{0 noTHz}} \cdot {(F_{1 THz} - F_{1 noTHz}) \cdot \exp [- i β (λ)] + (F_{1 THz}^{*} - F_{1 noTHz}^{*}) \cdot \exp [i β (λ)]} \propto E_{THz, ∥} (ω),

(10a)

View in Article

φ_{THz, ⊥} (ω) \to φ_{THz, ⊥} (λ) \approx \frac{2 i}{F_{0 noTHz}} \cdot {(F_{1 THz} - F_{1 noTHz}) \cdot \exp [- i β (λ)] - (F_{1 THz}^{*} - F_{1 noTHz}^{*}) \cdot \exp [i β (λ)]} \propto E_{THz, ⊥} (ω) .

(10b)

View in Article

F_{0} = S_{0} (λ), F_{1} = \frac{1}{2} [S_{1} (λ) - i \cdot S_{2} (λ)] \exp [i β (λ)], F_{1}^{*} = \frac{1}{2} [S_{1} (λ) + i \cdot S_{2} (λ)] \exp [- i β (λ)] .

(11)

View in Article

E_{THz, ∥} (t) \propto \arg {\frac{\int_{- \infty}^{- \infty} A_{p} (ω) \exp {i [φ_{p} (ω) + φ_{THz, ∥} (ω)]} d ω}{\int_{- \infty}^{- \infty} A_{p} (ω) \exp [i φ_{p} (ω)] d ω}},

(12a)

View in Article

E_{THz, ⊥} (t) \propto \arg {\frac{\int_{- \infty}^{- \infty} A_{p} (ω) \exp {i [φ_{p} (ω) + φ_{THz, ⊥} (ω)]} d ω}{\int_{- \infty}^{- \infty} A_{p} (ω) \exp [i φ_{p} (ω)] d ω}} .

(12b)

View in Article

Figures&Tables (8)

References (29)

Copy Citation Text

Qinggang Lin, Xinming Yuan, Xuanke Zeng, Yatao Yang, Yi Cai, Xiaowei Lu, Maijie Zheng, Congying Wang, Wenhua Cao, Shixiang Xu. Single-shot terahertz polarization detection based on terahertz time-domain spectroscopy[J]. Photonics Research, 2022, 10(6): 1374

Download Citation

Set citation alerts for the article

Set citation alerts for the article

Save the article for my favorites

Paper Information

Recommended Topics

laser devices and laser physics

Lasers and Laser Optics

laser manufacturing

Instrumentation, Measurement and Metrology

Set citation alerts for the article

Please enter your email address