Narrow-band and tunable intense terahertz pulses for mode-selective coherent phonon excitation

Vicario, C.; Trisorio, A.; Allenspach, Stephan; Rüegg, Christian; Giorgianni, F.

doi:10.1063/5.0015612

Cited by 22 publications

(15 citation statements)

References 26 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The chirp-and-delay approach has already been successfully applied to several benchmark organic crystals, such as HMQ-TMS, DSTMS, and OH1, [43,47,[131][132][133] and the results demonstrate that a large tuning range of the generated THz pulses up to 7 THz (refer to Figure 11 [131] ), narrow bandwidth below 0.1 THz, and high field strength of several megavolts per centimeter can be achieved using this approach (also refer to an overview provided [132] ). Therefore, the advantage of using organic NLO crystals for multicycle narrowband THz pulse generation is similar to that for other schemes used for THz wave generation, i.e., the methods can achieve high THz pulse energies and a very broad tuning range of the central frequency.…”

Section: Narrowband Thz Generation By Optical Rectificationmentioning

confidence: 96%

Highly Nonlinear Optical Organic Crystals for Efficient Terahertz Wave Generation, Detection, and Applications

Kim

Kang

Puc

et al. 2021

Advanced Optical Materials

View full text Add to dashboard Cite

ordering in the crystalline state should be simultaneously considered when designing organic π-conjugated crystals to achieve the desired physical properties. However, the prediction of the molecular ordering of organic π-conjugated chromophores in the crystalline state is still significantly difficult. This is because most organic π-conjugated chromophores exhibit several complex intermolecular and intramolecular interactions (and interionic interactions) with multiple possible molecular conformations during the self-assembling process in the crystalline state. [17,18] For each specific target application, a different targeted control of the molecular ordering of chromophores in the crystalline state is required, which is still an important issue in the molecular (and crystal) engineering of various organic π-conjugated crystalline materials.This issue is more critical for organic nonlinear optical (NLO) crystals and will be the focus of this review. Organic NLO crystals can be used in diverse nonlinear photonic applications, such as frequency down-and up-conversion, terahertz (THz) wave generation and detection, phase and amplitude electro-optic modulation, and high-speed telecommunication integrated optics. [19][20][21][22][23] Organic crystals must possess a noncentrosymmetric molecular ordering of chromophores to achieve second-order optical nonlinearity. However, in addition to the aforementioned complicated molecular interactions, the introduction of strong polar substituents (electron-donating groups (EDGs) and electron-withdrawing groups (EWGs)) on widely used push-pull π-conjugated chromophores to increase their molecular nonlinearity also increases their dipole moment. In many cases, a high dipole moment leads to a centrosymmetric ordering of chromophores with antiparallel dipole-dipole aggregation in the crystalline state (i.e., there is no macroscopic second-order optical nonlinearity). This tendency further complicates the development of new organic NLO crystals with large second-order optical nonlinearity. This is one of the reasons for only a few classes of organic crystals with state-of-theart optical nonlinearity being reported in the last few decades. Moreover, in addition to large macroscopic second-order optical nonlinearity, different NLO applications require different targeted physical properties (e.g., refractive index, dispersion of the refractive index, dielectric constant, and absorption coefficient) and crystal characteristics (e.g., direction of the polar axis, morphology, aperture size, thickness, and facets). Therefore, it Organic π-conjugated crystals with second-order optical nonlinearity are considerably attractive materials for diverse terahertz (THz) wave photonics. An overview of the research of organic nonlinear optical (NLO) crystals for THz wave generation, detection, and applications is provided here. First, the status of organic NLO crystals compared to other alternative THz materials is described. Second, the basic theory and requirements for organic THz generators and d...

show abstract

Section: Narrowband Thz Generation By Optical Rectificationmentioning

confidence: 96%

Highly Nonlinear Optical Organic Crystals for Efficient Terahertz Wave Generation, Detection, and Applications

Kim

Kang

Puc

et al. 2021

Advanced Optical Materials

View full text Add to dashboard Cite

show abstract

“…Although, spectrally tunable THz signal have been observed, the strength of the signal are usually weaker compared to unshaped THz signal. The need for sufficiently high THz field strength and energy to stimulate nonlinear interactions for practical applications have only been realized with organic nonlinear crystals [20][21]. These crystals has the potential to yield intense THz pulses with wide spectra range.…”

Section: Ofmentioning

confidence: 99%

A Proposed Experimental Scheme for the Generation of Tunable THz Spectral at Narrow Bandwidth via Two Color Laser Induced-Plasma

Ojo¹

2023

Preprint

View full text Add to dashboard Cite

Modifiable THz spectral shapes are important tools that facilitate the comprehensive study of phonon dynamics in condensed matter systems. The generation of narrow bandwidth THz spectra with tunable center frequency which are suitable THz forms needed to achieve such objectives are currently less studied from the table top laser-induced plasma emitters’ perspective. This experimental research is aimed at developing a robust two-color laser induced plasma set-up comprising of a temporal pulse stretcher and an Optical Parametric Amplifier that generates chirped and wavelength tunable pulses respectively. By focusing and independently controlling the ω and 2ω arms of the chirped pulses resulting after the interaction with a β-BBO crystal, I aim to generate narrow bandwidth THz signal (from plasma) scalable at MV/cm intensity and tunable in a wide THz spectral range, in addition to varying the frequency ratio mix.

show abstract

“…However, using EFISH to quantify the 𝜒𝜒 (3) of materials is difficult in the "new terahertz (THz) gap", i.e., the frequency range of 5-15 THz, which are the phonon bands of many solid-state materials and functional groups, due to the limited access to high-field sources [16]. Recent progress in THz optics has enabled rich nonlinear spectroscopy and imaging techniques based on bright tabletop THz sources [17][18][19][20][21][22][23][24], yet to date, phase-sensitive TEFISH can only be performed for crystals without centrosymmetry, whose second harmonic generation (SHG) can serve as an local oscillator (LO) to interfere with the TEFISH emission [25].…”

Section: Introductionmentioning

confidence: 99%

Sub-wavelength, phase-sensitive microscopy of third-order nonlinearity in terahertz frequencies

Zhu¹,

Lin²,

Xu³

et al. 2023

Preprint

View full text Add to dashboard Cite

The third-order nonlinear susceptibility χ³ occurs universally in materials and can provide label-free fingerprint of materials’ electronic, vibrational, and structural information. One quantitative spectroscopic method to access low-energy resonances of χ³ is the terahertz electric field induced second harmonic generation (TEFISH), particularly suitable for centrosymmetric materials without second-order processes. However, quantifying TEFISH requires light sources with high spectral intensity, which is challenging for the “new terahertz gap” frequencies between 5-15 THz that, not by coincidence, is the fingerprint phonon bands for many solid-state materials. Here we report the realization of phase-sensitive heterodyne TEFISH microscopy offering simultaneous temporal, spectral, and spatial resolution in the frequency range of 4 to 18 THz for the first time. Using chirped pulse difference frequency generation, ee generated intense and frequency-tunable narrowband terahertz fields, and then demonstrated time-resolved hyperspectral TEFISH microscopy in polymer thin films (SU-8), 2D crystalline semiconductors (MoS₂), and a sub-wavelength terahertz resonator. By interfering the nonlinear emission with a local oscillator field, we retrieved both the amplitude and sign of TEFISH, quantitatively resolved the nonlinear spectra, and observed the resonance features of the samples with high sensitivity. The spatial resolution is much better than the diffraction limit of the terahertz excitation due to the short wavelength of the visible TEFISH signal. Our compact implementation of TEFISH allows ultrafast time-domain imaging of vibrational and polaritonic resonances in micro- and nanoscale quantum materials.

show abstract

Narrow-band and tunable intense terahertz pulses for mode-selective coherent phonon excitation

Cited by 22 publications

References 26 publications

Highly Nonlinear Optical Organic Crystals for Efficient Terahertz Wave Generation, Detection, and Applications

Highly Nonlinear Optical Organic Crystals for Efficient Terahertz Wave Generation, Detection, and Applications

A Proposed Experimental Scheme for the Generation of Tunable THz Spectral at Narrow Bandwidth via Two Color Laser Induced-Plasma

Sub-wavelength, phase-sensitive microscopy of third-order nonlinearity in terahertz frequencies

Contact Info

Product

Resources

About