69 citations · 372 across the 21 of their papers we have counts for
21 papers
Strong coupling of virtual negative states in the Kapitza-Dirac effect
Qianlong Wang, Sven Ahrens, Baifei Shen
Negative states are an intrinsic property of relativistic quantum theory and related to anti-particles in the context of the Dirac sea concept. We show that negative states can dom…
Gravitational photon echo
Wen-Te Liao, Sven Ahrens
The generation, controls, and storage of the gravitationally induced photon echo using the 8.4 eV Thorium-229 nuclear clock transition on Earth are theoretically investigated. With…
Parameter space investigation for spin-dependent electron diffraction in the Kapitza-Dirac effect
Yang Wang, Sven Ahrens
We demonstrate that spin-dependent electron diffraction is possible for a smooth range of transverse electron momenta in a two-photon Bragg scattering scenario of the Kapitza-Dirac…
Two-dimensional simulation of the spin-flip in the Kapitza-Dirac effect
Ping Ge, Sven Ahrens, Baifei Shen
Many calculations in strong field quantum field theory are carried out by using a simple field geometry, often neglecting the spacial field envelope. In this article, we simulate t…
Perturbative solution approach for computing the two-photon Kapitza-Dirac effect in a Gaussian beam standing light wave
Sven Ahrens, Chong Zhang, Ping Ge +2
Theoretical spin properties of the Kapitza-Dirac effect beyond the plane-wave description are not known in detail. We develop a method for computing electron diffraction of the two…
Gravitationally sensitive structured x-ray optics using nuclear resonances
Shin-Yu Lee, Sven Ahrens, Wen-Te Liao
Einstein's general theory of relativity not only revolutionized human understanding of the universe, but also brought many gravitational applications in large scale, such as gravit…
Beam focus and longitudinal polarization influence on spin dynamics in the Kapitza-Dirac effect
Sven Ahrens, Ziling Guan, Baifei Shen
We theoretically investigate the influence of a longitudinal laser polarization component from beam focusing on spin dynamics in Kapitza-Dirac scattering by solving the relativisti…
Spin-dependent two-photon Bragg scattering in the Kapitza-Dirac effect
Sven Ahrens, Zhenfeng Liang, Tilen Cadez +1
We present the possibility of spin-dependent Kapitza-Dirac scattering based on a two-photon interaction only. The interaction scheme is inspired from a Compton scattering process,…
Spin in Compton scattering with pronounced polarization dynamics
Sven Ahrens, Chang-Pu Sun
We theoretically investigate a scattering configuration in Compton scattering, in which the orientation of the electron spin is reversed and simultaneously, the photon polarization…
Electron spin filter and polarizer in a standing light wave
Sven Ahrens
We demonstrate the theoretical feasibility of spin-dependent diffraction and spin-polarization of an electron in two counter-propagating, circularly polarized laser beams. The spin…
Simulation of Zitterbewegung by modelling the Dirac equation in Metamaterials
Sven Ahrens, Jun Jiang, Yong Sun +1
We develop a dynamic description of an effective Dirac theory in metamaterials, in which the wavefunction is modeled by the corresponding electric and magnetic field in the metamat…
Spin dynamics in relativistic light-matter interaction
Heiko Bauke, Sven Ahrens, Christoph H. Keitel +1
Various spin effects are expected to become observable in light-matter interaction at relativistic intensities. Relativistic quantum mechanics equipped with a suitable relativistic…
Gravitational and Relativistic Deflection of X-Ray Superradiance
Wen-Te Liao, Sven Ahrens
Exploring Einstein's theories of relativity in quantum systems, for example by using atomic clocks at high speeds can deepen our knowledge in physics. However, many challenges stil…
Electron-spin dynamics in elliptically polarized light waves
Heiko Bauke, Sven Ahrens, Rainer Grobe
We investigate the coupling of the spin angular momentum of light beams with elliptical polarization to the spin degree of freedom of free electrons. It is shown that this coupling…
Relativistic spin operators in various electromagnetic environments
Heiko Bauke, Sven Ahrens, Christoph H. Keitel +1
Different operators have been suggested in the literature to describe the electron's spin degree of freedom within the relativistic Dirac theory. We compare concrete predictions of…
Electron-spin dynamics induced by photon spins
Sven Ahrens, Heiko Bauke, Christoph H. Keitel +1
Strong rotating magnetic fields may cause a precession of the electron's spin around the rotation axis of the magnetic field. The superposition of two counterpropagating laser beam…
Spin effects in strong-field laser-electron interactions
S. Ahrens, T. O. Müller, S. Villalba-Chávez +2
The electron spin degree of freedom can play a significant role in relativistic scattering processes involving intense laser fields. In this contribution we discuss the influence o…
Computational relativistic quantum dynamics and its application to relativistic tunneling and Kapitza-Dirac scattering
Heiko Bauke, Michael Klaiber, Enderalp Yakaboylu +4
Computational methods are indispensable to study the quantum dynamics of relativistic light-matter interactions in parameter regimes where analytical methods become inapplicable. W…
Kapitza-Dirac effect in the relativistic regime
Sven Ahrens, Heiko Bauke, Christoph H. Keitel +1
A relativistic description of the Kapitza-Dirac effect in the so-called Bragg regime with two and three interacting photons is presented by investigating both numerical and perturb…
What is the relativistic spin operator?
Heiko Bauke, Sven Ahrens, Christoph H. Keitel +1
Although the spin is regarded as a fundamental property of the electron, there is no universally accepted spin operator within the framework of relativistic quantum mechanics. We i…
Spin dynamics in the Kapitza-Dirac effect
Sven Ahrens, Heiko Bauke, Christoph H. Keitel +1
Electron spin dynamics in Kapitza-Dirac scattering from a standing laser wave of high frequency and high intensity is studied. We develop a fully relativistic quantum theory of the…