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We review recent studies of cavity switching induced by the optical injection of free carriers in micropillar cavities containing quantum dots. Using the quantum dots as a broadband internal light source and a streak camera as detector, we track the resonance frequencies for a large set of modes with picosecond time resolution. We report a record-fast switch-on time constant (1.5 ps) and observe major transient modifications of the modal structure of the micropillar on the 10 ps time scale: mode crossings are induced by a focused symmetric injection of free carriers, while a lifting of several mode degeneracies is observed when off-axis injection breaks the rotational symmetry of the micropillar. We show theoretically and experimentally that cavity switching can be used to tailor the dynamic properties of the coupled QD–cavity system. We report the generation of ultrashort spontaneous emission pulses (as short as 6 ps duration) by a collection of frequency-selected QDs in a switched pillar microcavity. These pulses display a very small coherence length, attractive for ultrafast speckle-free imaging. Moreover, the control of QD-mode coupling on the 10 ps time scale establishes cavity switching as an appealing resource for quantum photonics.

We present a table-top extreme ultraviolet (XUV) beamline for measuring time- and frequency-resolved XUV-excited optical luminescence (XEOL) with additional femtosecond-resolution XUV transient absorption spectroscopy functionality. XUV pulses are generated via high-harmonic generation using a near-infrared pulse in a noble gas medium and focused to excite luminescence from a solid sample. The luminescence is collimated and guided into a streak camera where its spectral components are temporally resolved with picosecond temporal resolution. We time-resolve XUV-excited luminescence and compare the results to luminescence decays excited at longer wavelengths for three different materials: (i) sodium salicylate, an often used XUV scintillator; (ii) fluorescent labeling molecule 4-carbazole benzoic (CB) acid; and (iii) a zirconium metal oxo-cluster labeled with CB, which is a photoresist candidate for extreme-ultraviolet lithography. Our results establish time-resolved XEOL as a new technique to measure transient XUV-driven phenomena in solid-state samples and identify decay mechanisms of molecules following XUV and soft-x-ray excitation.

Due to the wave characteristics of light, diffraction occurs when the light passes through the optical system, so that the resolution of the ordinary far-field optical system is limited by the size of the Airy disk diameter. There are various factors that cause image quality degradation during system detection and imaging, such as optical system aberrations, atmospheric inter-ference, defocusing, system noise and so on. Super-resolution optical imaging technology is the most innovative breakthrough in the optical imaging and detection field in this century. It goes beyond the resolution limit of ordinary optical systems or detectors, and can get more details and information of the structure, providing unprecedented tools for various fields. Compared with ordinary optical systems, super-resolution systems have very high requirements on the signals to be detected, which cannot be met by ordinary detection techniques. Vacuum photoelectric detection and imaging technology is equipped with the characteristics of high sensitivity and fast response. It is widely used in super-resolution systems and has played a great role in super-resolution systems. In this paper, the principles and structure of the image-converter streak camera super-resolution system, scanning electron microscopy super-resolution system and laser scanning confocal super-resolution system will be sorted out separately, and the essential role of the vacuum photoelectric detection technology in the ultra-microscopic sys-tem will be analyzed.

We propose a high temporal resolution numerical algorithm for shock wave velocity diagnosis. By analysing variations in the optical path and phasor of a light field, we determine a high temporal resolution shock wave velocity equation for a velocity interferometer system for any reflector (VISAR). The equation can be transformed into matrix form for numerical solution. To solve noise problems, a ‘filtering velocity spectrum’ method is proposed. Analysis of a VISAR data example shows that the resolution precision of shock wave velocity obtained from the numerical algorithm is the same as the temporal resolution of a streak camera. Moreover, it can observe the shock wave in greater detail. This algorithm can be used to observe detailed images and determine the mechanism and evolution of extreme shock waves, as well as provide data for research into hydrodynamic behaviour in inertial confinement fusion.

The spatiotemporal measurement of the ultrashort laser pulses is of great significance in the diagnosis of the instrument performance and the exploration of the laser and matter interaction. In this work, we report an advanced compressed ultrafast photography (CUP) technique to measure the spatiotemporal intensity distribution of the picosecond laser pulses with a single shot. This CUP technique is based on a three-dimensional image reconstruction strategy by employing the random codes to encode the space-time-evolving laser pulse and decode it based on a compressed sensing (CS) algorithm. In our CUP system, the measurable laser wavelength depends on the spectral response of the streak camera, which can cover a wide range from ultraviolet (200 nm) to near infrared (850 nm). Based on the CUP system we develop, we successfully measure the spatiotemporal intensity evolutions of some typical laser pulses, such as the 800 nm picosecond laser pulse, the 800 and 400 nm two-color picosecond laser pulses and the supercontinuum picosecond laser pulse. These experimental results show that the CUP technique can well characterize the spatiotemporal intensity information of the picosecond laser pulses. Moreover, this technique has the remarkable advantages with the single shot measurement and without the reference laser pulse.

Axial radiation properties of Z-pinch dynamic hohlraum have been investigated experimentally on JULONG-I facility in China. A new method of time resolved temperature diagnostics in dynamic hohlraum experiments has been developed via a one-dimensional (1-D) imaging system consisting of a streak camera. With the help of the axial radiation power profile measured by an X-ray power measurement system using the same type of scintillator as in the 1-D imaging system, time resolved temperature distribution along the one-dimensional space in dynamic hohlraum experiments are extracted by a special mathematical transform process of the image. The peak radiation temperature in the centre is more than 100 eV. The radiation temperatures are also estimated by the 1-D Multi-IFE-Z program.

Luminescence lifetime detection plays an important role in time-resolved detection and research. However, the traditional instruments always require expensive detectors such as time-correlated single photon counter or streak camera. Herein, a low-cost and miniaturized apparatus for measuring upconversion luminescence lifetimes was developed by using a smartphone equipped with a 980 nm CW laser and a motor. When the motor was driving the sample circling at a high linear velocity, the excited sample would emit a luminescence arc, which could be photographed by the phone camera. The rotating rate could be measured by a tuner APP and then used for transferring arc length to delay times. By analyzing the grayscale distribution of the luminescence arc, the luminescence decay curve was obtained, which was then used for exponential fit and calculating lifetimes. The images captured by different smartphones revealed similar lifetime values, suggesting a wide universality of this method. The whole system was not only remarkably cheaper but also more miniaturized than traditional instruments for measuring luminescence lifetimes, indicating the promising applications in point of care testing for time-resolved luminescence detection for bioanalysis and disease diagnosis.

The results of the development of a technique for measuring the power contrast of a laser pulse by registering the pulse-front profile with a large dynamic range are presented. The technique was developed on the basis of a high-speed streak camera and fiber-optic transmission lines; it provides the following registration parameters: the dynamic range of measuring the laser-pulse power contrast at the wavelength λ = 0.53 µm is 107, while the temporal resolution of the registration channel is no worse than 60 ps. A method of increasing the power contrast to 1011 using an optical scheme based on elements with nonlinear transmission is shown.

The physics of vacuum arc spot operation remains subject of research due to difficulties associated with short characteristic times (ns to μs) and short length scales (μm or even smaller). The advancement of modern plasma diagnostic technologies may allow us to probe arc spot plasma with higher spatial and temporal resolution than before. In this contribution, we report on the evolution of arc spots using a steered arc plasma source which is in its construction similar to a linear sputtering magnetron: the E x B field is utilized to have some control of spot locations while performing the study. The main plasma diagnostics tool we employ is a streak camera with an image intensifier which allows us to observe the dynamics of the optical emission of arc spots in various sweep time intervals (50 μs, 10 μs, 1 μs, and 500 ns). The observed spot shows self-similar patterns in the emitted light with different sweep times.

We are planning detailed spectroscopic studies of the X-ray bursts produced by hybrid X-pinches using a ~20 ps time resolution X-ray streak camera and ~700 ps resolution filtered silicon diodes. The purpose is to investigate whether the X-ray spectroscopic features associated with radiative collapse can be seen in the X-ray bursts produced by the Hybrid X-pinches. A nickel wire has been used as the load and time integrated L and K-shell spectra were recorded on imaging plates. In addition, silicon diodes were focused on specific emission lines from the X-ray spectrometer crystals to track their intensity evolution. Time-resolved temperature and density measurements can be estimated throughout the implosion and expansion phases from these diagnostics. Time-resolved source size measurements are also being carried out using the ~20 ps time resolved streak camera to determine the change of the spot size on a picosecond timescale. Sufficiently high magnification studies are being carried to determine the source size in the 1-10 µm range.

Recent MagLIF experiments at the NIF have measured the energy coupling and propagation of a ~35 kJ laser pulse in 1 cm-long gas pipe targets with hydrocarbon gas fills and pre- imposed magnetic fields

Observations of optical synchrotron radiation emitted over millions of passes from a few electrons circulating in the particle accumulator ring at the Advanced Photon Source were performed with a digital CMOS camera and a synchroscan streak camera operating at 117.3 MHz. Discrete changes of integrated counts in the CMOS image region of interest are ascribed to single electron steps in a 10-s sensor integration time. Circulations of a single electron at 375 and at 425 MeV were demonstrated in the 12-bit digital CMOS camera images. The streak camera operating at the 12th harmonic of the fundamental revolution frequency at 9.77 MHz was used to measure the bunch length from 0.5-nC circulating charge down to tens of electrons or $l10\text{ }\text{ }\mathrm{aC}$. The measurements were performed with $\ensuremath{\sim}8\text{\ensuremath{-}}\mathrm{ps}$ temporal resolution uniquely at such ultralow charges. These results also serve as a proof-of-principle longitudinal profile diagnostic for the predicted effects of optical stochastic cooling at low charge in commissioning experiments at the Fermilab Integrable Optics Test Accelerator ring.

We develop a compressed-sensing two-dimensional rotating-mirror streak camera that enables single-shot ultrahigh-speed optical imaging with a speed of up to 1.5 million frames per second. Using this technique, we have imaged a single laser pulse illuminating through a transmissive target.

The results of the study of the flow formation and its dynamics in the plasma focus discharge on the PF-3 facility using the streak camera are presented. To study the propagation of the flow in the background plasma and its structure, the facility has a three-section flight chamber. A comparison of the optical streaks obtained in the pinching region with the images obtained using frame cameras shows that at the final stage of pinching, a bright object can be observed over the current sheath, which we associate with the incipient flow. Measurements in the flight chamber showed that the flow has a complex structure, possibly related to the development of instabilities. When an external poloidal magnetic field is applied, the flow becomes more compact and the radiation intensity of the flow increases.