Article
Physics, Fluids & Plasmas
Henry Fetsch, Nathaniel J. Fisch
Summary: The fast ignition paradigm in inertial fusion offers higher gain and ability to tolerate asymmetry by compressing low entropy fuel and rapidly igniting a small region. This study presents a pulse shape to maximize ion heating using a simple model of a hot spot in isochoric plasma, which allows for a smaller hot spot and improved fusion gain.
Article
Optics
Vladimir Ya Molchanov, Konstantin B. Yushkov, Pavel Kostryukov, Petr B. Gornostaev, Nikolay S. Vorobiev
Summary: This study in the field of ultrafast optics experimentally investigated acousto-optic pulse shaping and found that the sign of the second order dispersion from the acousto-optic dispersion delay line impacts modulation rise/fall time. By comparing different algorithms, the researchers achieved a minimum modulation rise/fall time for 3mJ pulses with linear chirp at 6.2 ps/nm at a wavelength of 795nm.
OPTICS AND LASER TECHNOLOGY
(2021)
Article
Optics
David Sohr, Jens Ulrich Thomas, Stefan Skupin
Summary: This study demonstrates curved modifications within borosilicate glass using a 1030 nm picosecond laser. Plasma ignition in the sidelobes of the beam and surface damage are identified as crucial limitations for confined bulk energy deposition. Through experimental and numerical analysis, optimum laser parameters for confined bulk energy deposition have been determined.
Article
Chemistry, Multidisciplinary
Rene Geromel, Philip Georgi, Maximilian Protte, Shiwei Lei, Tim Bartley, Lingling Huang, Thomas Zentgraf
Summary: Dispersion is a common phenomenon in optical systems and is often undesirable, especially in nonlinear-optical experiments requiring ultrashort laser pulses. A compact pulse-shaping device using plasmonic metasurfaces is introduced to achieve full dispersion control by applying a designed spectral phase delay. Additionally, the device can reshape incident laser pulses into more complex forms, such as a double pulse, through specific phase encodings. The device's performance is verified using an SHG-FROG measurement setup and a retrieval algorithm to extract the dispersion applied to the incident laser pulse.
Article
Optics
L. Chen, P. Huo, J. Song, Z. Wang, T. Xu, W. Zhu, A. Agrawal
Summary: Research has found that the polarization state of light is crucial in revealing intrinsic chiral or anisotropic optical response in various material systems, and is important for applications requiring complex polarization encoding. By leveraging the nanoscale multidimensional control of light offered by metasurfaces, we can engineer the temporal evolution of the instantaneous polarization state of a femtosecond pulse through parallel manipulation of its constituent spectral components across an ultrawide bandwidth. We expect this control over the synthesis of complex vectorially shaped pulses to further elucidate ultrafast chiral light-matter interactions.
Article
Optics
Zhiyuan Jia, Peilei Zhang, Zhishui Yu, Haichuan Shi, Hongbing Liu, Di Wu, Xin Ye, Fuxin Wang, Yingtao Tian
Summary: Different pulse shaping designs can effectively improve the solidification condition of aluminum alloy pulsed laser welding spots, reducing the risk of solidification cracks.
OPTICS AND LASER TECHNOLOGY
(2021)
Article
Multidisciplinary Sciences
Geoffrey Gaulier, Quentin Dietschi, Swarnendu Bhattacharyya, Cedric Schmidt, Matteo Montagnese, Adrien Chauvet, Sylvain Hermelin, Florence Chiodini, Luigi Bonacina, Pedro L. Herrera, Ursula Rothlisberger, Ivan Rodriguez, Jean-Pierre Wolf
Summary: Experiments have shown that the initial step of vision involves ultra-fast photoisomerization controlled by shaping the phase of femtosecond laser pulses. The electric signals fired from the retina of living mice in response to light stimulation on a femtosecond time scale were found to be sensitive to manipulation of light excitation. This sensitivity is attributed to interactions with light pulses near conical intersections, involving processes like pump-dump and pump-repump.
Article
Computer Science, Information Systems
Junlong Wu, Xianguo Tuo
Summary: This paper introduces the widely used trapezoidal shaping method in digital nuclear spectroscopy and its advantages, and proposes a new recursive algorithm to improve the anti-pulse pile-up ability.
Article
Automation & Control Systems
Shanshan Jin, Jindong Chen, Zhibin Li, Chunhui Zhang, Yajun Zhao, Zhi Fang
Summary: This article introduces a high-voltage pulse current power supply (HV-PCPS) based on RDD shaping method, which can solve the problem of poor waveform quality, ensure stable discharge, and limit the maximum output voltage amplitude. The effectiveness of the proposed method is verified through a 30kV HV-PCPS prototype.
IEEE TRANSACTIONS ON INDUSTRIAL ELECTRONICS
(2022)
Article
Engineering, Manufacturing
Danilo de Camargo Branco, Eshan Ganju, Licong An, Nikhilesh Chawla, Gary J. Cheng
Summary: The Powder Bed Fusion (PBF) additive manufacturing technique is widely used in the industry but has issues of porosity and lack of fusion. This study focuses on controlling the transient temperature field by shaping the laser pulse to improve build quality and reduce defects.
ADDITIVE MANUFACTURING
(2023)
Article
Optics
Kevin F. Lee, Antoine Rolland, Peng Li, Jie Jiang, Martin E. Fermann
Summary: In this study, we shape the spectrum of a supercontinuum spanning an octave using an erbium fiber laser. By controlling the temperature profile of a chirped fiber Bragg grating, we demonstrate control over spectral broadening, switching in spectral windows, and power optimization. We verify the locking of the shaped f-2f beat note and the coherence of the shaped supercontinuum through interference measurements.
Article
Oncology
Eric J. Roeland, Kari Bohlke, Vickie E. Baracos, Thomas J. Smith, Charles L. Loprinzi
Summary: ASCO Rapid Recommendations Updates revise guideline recommendations in response to new and practice-changing data, with the goal of providing the best available cancer care options to health practitioners and the public.
JOURNAL OF CLINICAL ONCOLOGY
(2023)
Article
Materials Science, Ceramics
Pallagani Jeevankumar, Poly Rose, Ammanabrolu Rajanikanth, Thankappan Pillai Rajasekharan, Vummethala Seshu Bai
Summary: Dense ceramic components of complex shapes can be fabricated using the RPGC process, which combines rapid prototyping and gelcasting techniques. EPS molds have advantages in easy demolding and near-net shaping, and result in components with uniform density and good mechanical properties.
INTERNATIONAL JOURNAL OF APPLIED CERAMIC TECHNOLOGY
(2023)
Article
Optics
Kun Chang, Longfei Zhu, Baoluo Yan, Guangke Jiang, Dengke Xing, Kaiyan Zhu, Jiangyong He, Luhe Zhang, Congcong Liu, Mengjie Zhou, Yange Liu, Zhi Wang
Summary: Spectral shaping is an effective solution for generating high-energy, short pulses in fiber chirped-pulse amplification systems. A spectral notch filter design based on genetic algorithm and parallel computing has been demonstrated, achieving over 97% overlap between amplified and seed spectra. This approach allows for compensation of spectral narrowing and shifting simultaneously.
Article
Materials Science, Multidisciplinary
Xinlin Wang, Han Yu, Jinkun Jiang, Chengui Xia, Zengxia Zhang
Summary: This study investigates the effects of pulse shaping on the geometrical characteristics, microstructure, and microhardness in laser material deposition (LMD). The results show that different laser shapes result in clads with different dimensions and properties.
Article
Optics
Jiahao Guo, Jiubin Tan, Pengcheng Hu, Steven T. Cundiff
Summary: Light propagation in arrays of AlxGa1-xAs waveguides was studied, with the power coupling constant between adjacent waveguides measured precisely. The polarization dependence of coupling constants was observed due to asymmetric effective refractive index between linearly polarized modes. Through careful geometric design, comparable coupling constants were achieved in three waveguide arrays with different structures.
Article
Multidisciplinary Sciences
Albert Liu, Diogo B. Almeida, Luiz G. Bonato, Gabriel Nagamine, Luiz F. Zagonel, Ana F. Nogueira, Lazaro A. Padilha, S. T. Cundiff
Summary: Advances in optoelectronics are driving the need for materials with novel characteristics, with metal-halide perovskites being a class of materials that has garnered significant interest. Recent research has focused on using perovskite nanocrystals in photovoltaic and light-emitting devices, revealing unique excitonic fine structures that contribute to efficient light emission. The study of cesium lead-halide perovskite nanocrystals through multidimensional coherent spectroscopy has provided insights into the fine structure level ordering of excitons within the bright triplet manifold.
Article
Chemistry, Multidisciplinary
Albert Liu, Gabriel Nagamine, Luiz G. Bonato, Diogo B. Almeida, Luiz F. Zagonel, Ana F. Nogueira, Lazaro A. Padilha, Steven T. Cundiff
Summary: Using multidimensional coherent spectroscopy, it was found that the line broadening mechanisms of perovskite nanoplatelets depend on platelet geometry, with decreasing thickness resulting in reduced line widths. Additionally, homogeneously broadened exciton resonances were observed in two-layer, but not necessarily three-layer, nanoplatelets at room temperature.
Article
Physics, Applied
Kelsey M. Bates, Matthew W. Day, Christopher L. Smallwood, Rachel C. Owen, Tim Schroder, Edward Bielejec, Ronald Ulbricht, Steven T. Cundiff
Summary: An ensemble of silicon vacancy (SiV-) centers in diamond was probed using two-pulse correlation spectroscopy and multidimensional coherent spectroscopy. Two main distinct families of SiV- centers were identified, and local strain tensor was calculated based on measured spectra. Variations in strain tensor were observed at multiple points on the sample surface.
JOURNAL OF APPLIED PHYSICS
(2021)
Article
Optics
Brad C. Smith, Bachana Lomsadze, Steven T. Cundiff
Summary: A spectrally precise and potentially rapid hyperspectral imaging technique based on four-wave mixing and frequency comb, demonstrated in near-diffraction-limited microscopy applications, can be applied to any material in principle.
Article
Physics, Multidisciplinary
Christopher L. Smallwood, Ronald Ulbricht, Matthew W. Day, Tim Schroeder, Kelsey M. Bates, Travis M. Autry, Geoffrey Diederich, Edward Bielejec, Mark E. Siemens, Steven T. Cundiff
Summary: A high-density sample of negatively charged silicon-vacancy (SiV-) centers in diamond was characterized using collinear optical multidimensional coherent spectroscopy, revealing a hidden population of SiV- centers with significant spectral inhomogeneity and extended electronic T-2 times, likely caused by strain and providing a potential mechanism for controlling electric coherence in color-center-based quantum devices.
PHYSICAL REVIEW LETTERS
(2021)
Article
Physics, Multidisciplinary
J. Guo, S. T. Cundiff, J. M. Soto-Crespo, N. Akhmediev
Summary: Concurrent passive mode-locked and self-Q-switched operation of laser devices is modeled using the complex cubic-quintic Ginzburg-Landau equation. Experimental observations show good qualitative agreement with the numerical results on the shape of each individual self-Q-switched pulse and the periodic trains of pairs of such pulses.
PHYSICAL REVIEW LETTERS
(2021)
Article
Chemistry, Physical
Torben L. Purz, Eric W. Martin, William G. Holtzmann, Pasqual Rivera, Adam Alfrey, Kelsey M. Bates, Hui Deng, Xiaodong Xu, Steven T. Cundiff
Summary: TMDs are considered as a potential material platform for quantum information science, and multi-dimensional coherent imaging spectroscopy sheds light on the underlying physics for both MoSe2 monolayers and MoSe2/WSe2 heterostructures. The study identifies promising and unfavorable areas for quantum information applications, highlighting the importance of robustness in coherent and incoherent coupling for device applications. The presence of strain and dielectric environment changes does not significantly affect the interlayer exciton lifetimes, supporting TMDs as a next-generation material platform in quantum information science and beyond.
JOURNAL OF CHEMICAL PHYSICS
(2022)
Article
Physics, Multidisciplinary
Matthew W. Day, Kelsey M. Bates, Christopher L. Smallwood, Rachel C. Owen, Tim Schroder, Edward Bielejec, Ronald Ulbricht, Steven T. Cundiff
Summary: We report on the tunable excitation-induced dipole-dipole interactions between silicon-vacancy color centers in diamond at cryogenic temperatures. These interactions couple the centers into collective states and allow for the tagging of the excitation level of these states. By analyzing the phase and amplitude of the spectra, we observed oscillations in the interaction strength and population state of the collective states. These findings demonstrate the potential of excitation-induced dipole-dipole interactions between color centers in manipulating collective intercenter states.
PHYSICAL REVIEW LETTERS
(2022)
Article
Optics
Torben L. Purz, Blake T. Hipsley, Eric W. Martin, Ronald Ulbricht, Steven T. Cundiff
Summary: In this study, rapid imaging based on four-wave mixing (FWM) is demonstrated for assessing the quality of advanced materials. The nonlinear response, exciton dephasing, and exciton lifetimes are measured to evaluate the material parameters. The results show that FWM technique provides a more accurate assessment of sample quality compared to current prevalent techniques. Future improvements of the ultrafast FWM techniques are discussed, including modeling the robustness of exponential decay fits. The use of ultrafast nonlinear imaging in real-time at room temperature has the potential for rapid in-situ sample characterization of advanced materials.
Review
Chemistry, Physical
Albert Liu, Diogo B. Almeida, Steven T. Cundiff, Lazaro A. Padilha
Summary: At low excitation densities, the interactions between excitons and the atomic lattice dominant the dynamics of semiconductor nanocrystals. Understanding and characterizing exciton-phonon coupling is crucial for guiding the design of colloidal nanocrystal materials and their device applications.
ELECTRONIC STRUCTURE
(2023)
Article
Chemistry, Physical
M. Elious Mondal, Eric R. Koessler, Justin Provazza, A. Nickolas Vamivakas, Steven T. Cundiff, Todd D. Krauss, Pengfei Huo
Summary: We have developed an accurate and numerically efficient method for simulating the non-linear spectroscopy of exciton-polariton systems. By investigating the influence of light-matter coupling strength and cavity loss rate on the optical response, we have confirmed the polaron decoupling effect and demonstrated the prolongation of polariton coherence time.
JOURNAL OF CHEMICAL PHYSICS
(2023)
Article
Materials Science, Multidisciplinary
Albert Liu, Diogo B. Almeida, Lazaro A. Padilha, Steven T. Cundiff
Summary: Colloidal perovskite nanocrystals (PNCs) have great potential for optoelectronic applications. Spectroscopic characterization is crucial for understanding their structure and device implementation. Multi-dimensional coherent spectroscopy (MDCS) can resolve exciton dynamics and reveal homogeneous spectral lineshapes, providing new possibilities for their application.
JOURNAL OF PHYSICS-MATERIALS
(2022)
Article
Materials Science, Multidisciplinary
Torben L. Purz, Eric W. Martin, Pasqual Rivera, William G. Holtzmann, Xiaodong Xu, Steven T. Cundiff
Summary: The study observed coherent coupling between excitons localized in monolayer MoSe2 and WSe2 in monolayer MoSe2/WSe2 heterostructures, as well as spectroscopic measurement of the interlayer exciton binding energy of about 250 meV.
Article
Materials Science, Multidisciplinary
Albert Liu, Steven T. Cundiff, Diogo B. Almeida, Ronald Ulbricht
Summary: Multi-dimensional coherent spectroscopy was applied to study the NV center ensemble in diamond at cryogenic temperatures, revealing thermal dephasing and ultrafast spectral diffusion. The intrinsic, ensemble-averaged homogeneous linewidth was found to be in the tens of GHz range by extrapolating to zero temperature, and a temperature-dependent Stark splitting of the excited state manifold relevant to NV sensing protocols was observed.
MATERIALS FOR QUANTUM TECHNOLOGY
(2021)
