Toward nonthermal control of excited quantum materials: framework and investigations by ultrafast electron scattering and imaging

Sun, Xiaoyi; Sun, Shuaishuai; Ruan, Chong‐Yu

doi:10.5802/crphys.86

Cited by 7 publications

(3 citation statements)

References 281 publications

(560 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…We could determine the LA mode amplitude based on the intensity modulation. 37 The ≈0.5% amplitude change, as observed in Fig. 10(b) , gives the coherent phonon amplitude at the level of 5 × 10 −4 Å.…”

Section: New Development In the Phase Precision Controlmentioning

confidence: 68%

“…The structure factor associated with the broken-symmetry CDW order,

, is given in the basis of the unmodified lattice form factor

where

denotes the position of the undistorted lattice. 37 The dynamical evolution shown in lattice and superlattice peaks are given by lattice displacement field

, depicted by two different types of lattice waves: the lattice phonons (

) or collective field modes of the broken-symmetry order (

) with momentum wavevector

and

given by

and

, referencing to the central Bragg reflection

.…”

Section: New Development In the Phase Precision Controlmentioning

confidence: 99%

See 1 more Smart Citation

Precision-controlled ultrafast electron microscope platforms. A case study: Multiple-order coherent phonon dynamics in 1T-TaSe2 probed at 50 fs–10 fm scales

Sun,

Williams,

Sharma

et al. 2024

Structural Dynamics

Self Cite

View full text Add to dashboard Cite

We report on the first detailed beam tests attesting the fundamental principle behind the development of high-current-efficiency ultrafast electron microscope systems where a radio frequency (RF) cavity is incorporated as a condenser lens in the beam delivery system. To allow for the experiment to be carried out with a sufficient resolution to probe the performance at the emittance floor, a new cascade loop RF controller system is developed to reduce the RF noise floor. Temporal resolution at 50 fs in full-width-at-half-maximum and detection sensitivity better than 1% are demonstrated on exfoliated 1T-TaSe2 system under a moderate repetition rate. To benchmark the performance, multi-terahertz edge-mode coherent phonon excitation is employed as the standard candle. The high temporal resolution and the significant visibility to very low dynamical contrast in diffraction signals via high-precision phase-space manipulation give strong support to the working principle for the new high-brightness femtosecond electron microscope systems.

show abstract

Section: New Development In the Phase Precision Controlmentioning

confidence: 68%

“…The structure factor associated with the broken-symmetry CDW order,

, is given in the basis of the unmodified lattice form factor

where

denotes the position of the undistorted lattice. 37 The dynamical evolution shown in lattice and superlattice peaks are given by lattice displacement field

, depicted by two different types of lattice waves: the lattice phonons (

) or collective field modes of the broken-symmetry order (

) with momentum wavevector

and

given by

and

, referencing to the central Bragg reflection

.…”

Section: New Development In the Phase Precision Controlmentioning

confidence: 99%

Precision-controlled ultrafast electron microscope platforms. A case study: Multiple-order coherent phonon dynamics in 1T-TaSe2 probed at 50 fs–10 fm scales

Sun,

Williams,

Sharma

et al. 2024

Structural Dynamics

Self Cite

View full text Add to dashboard Cite

show abstract

“…Ultrafast structural processes that occur following excitation can be visualized [41][42][43] and cross-checked [44] adopting both real-space (imaging) and reciprocal-space (diffraction) approaches for a UTEM, providing atomic and morphological information with femtosecond time resolution. Using ultrafast selected-area electron diffraction (USAED), one can get both the mean atomic displacements of short-range order following the Debye-Waller relation (i.e., the diffraction intensity change of the main Bragg peak) and the crystal lattice change of long-range order with precision of 10 −4 nm (i.e., the position shift of the Bragg peak).…”

Section: Ultrafast Structural Dynamics and Phase Transitions Revealed...mentioning

confidence: 99%

Capturing the non-equilibrium state in light–matter–free-electron interactions through ultrafast transmission electron microscopy

Wang 汪,

Sun 孙,

Li 李

et al. 2023

Chinese Phys. B

View full text Add to dashboard Cite

Ultrafast transmission electron microscope (UTEM) with the multimodality of time-resolved diffraction, imaging, and spectroscopy provides a unique platform to reveal the fundamental features associated with the interaction between free electrons and matter. In this review, we summarize the principles, instrumentation, and recent developments of the UTEM and its applications in capturing dynamic processes and non-equilibrium transient states. The combination of the transmission electron microscope with a femtosecond laser via the pump–probe method guarantees the high spatiotemporal resolution, allowing the investigation of the transient process in real, reciprocal and energy space. Ultrafast structural dynamics can be studied by diffraction and imaging methods, revealing the coherent acoustic phonon generation and photo-induced phase transition process. In the energy dimension, time-resolved electron energy-loss spectroscopy enables the examination of the intrinsic electronic dynamics of materials, while the photon-induced near-field electron microscopy extends the application of the UTEM to the imaging of optical near fields with high real-space resolution. It is noted that light–free-electron interactions have the ability to shape electron wave packets in both longitudinal and transverse directions, showing the potential application in the generation of attosecond electron pulses and vortex electron beam.

show abstract

The Many Facets of Ultrafast Electron Diffraction and Microscopy: Development and Applications

Ruan

2023

Structural Dynamics With X-Ray and Electron Scattering

View full text Add to dashboard Cite

In the past two decades, the rapid pace in the development of table-top ultrafast electron diffraction and microscopy instrumentation has ushered in a new area of investigating structural dynamics and related material property responses. In this chapter, we will review the multifaceted development involving gas-phase ultrafast electron diffraction for investigating photochemistry (gas phase UED), surface-sensitive ultrafast electron nanocrystallography (UEnC) and ultrafast photovoltamnetry (UPV) for probing subsurfaces, surfaces, and supported nanoparticles, as well as ultrafast electron crystallography (UEC) for the studies of molecular crystals and quantum materials. Prototypical examples of data collections, core technologies, and specialized protocols for structure analysis are presented in some detail with the hope that they can be reproduced by interested readers in their own studies. The need to simultaneously obtain information about the electronic states, functionalities, as well as structure dynamics motivates the development of ultrafast electron microscopy (UEM) in which diffraction, imaging, and spectroscopy are united to enable multimodality observations on ultrafast timescales for a broad range of materials science problems. The second part of the chapter covers the latest UEM technologies supported by new developments in generating high-brightness electron bunches, and the RF-based techniques for phase-space manipulations. Based on current progress, frank assessments about the performance in different areas and limitations are provided.

show abstract

Toward nonthermal control of excited quantum materials: framework and investigations by ultrafast electron scattering and imaging

Abstract: Toward nonthermal control of excited quantum materials: framework and investigations by ultrafast electron scattering and imaging

Cited by 7 publications

References 281 publications

Precision-controlled ultrafast electron microscope platforms. A case study: Multiple-order coherent phonon dynamics in 1T-TaSe2 probed at 50 fs–10 fm scales

Precision-controlled ultrafast electron microscope platforms. A case study: Multiple-order coherent phonon dynamics in 1T-TaSe2 probed at 50 fs–10 fm scales

Capturing the non-equilibrium state in light–matter–free-electron interactions through ultrafast transmission electron microscopy

The Many Facets of Ultrafast Electron Diffraction and Microscopy: Development and Applications

Contact Info

Product

Resources

About