Electric-dipole-forbidden nuclear transitions driven by super-intense laser fields

Pálffy, Adriana; Evers, Jörg; Keitel, Christoph H.

doi:10.1103/physrevc.77.044602

Cited by 58 publications

(85 citation statements)

References 49 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Similar possibilities with nuclear systems have been considered with great interest [1][2][3][4][5][6][7][8] already shortly after the realization of the first laser in the optical band [9]. However, many quantum optical control schemes require the effective coupling of the driving field to the considered transition (Rabi frequency) to be of the same order as the relaxation rate of the same transition [10,11].…”

mentioning

confidence: 99%

Coherent control of the cooperative branching ratio for nuclear x-ray pumping

2011

Self Cite

View full text Add to dashboard Cite

Coherent control of nuclear pumping in a three level system driven by x-ray light is investigated. In single nuclei, the pumping performance is determined by the branching ratio of the excited state populated by the x-ray pulse. Our results are based on the observation that in ensembles of nuclei, cooperative excitation and decay leads to a greatly modified nuclear dynamics, which we characterize by a time-dependent cooperative branching ratio. We discuss prospects of steering the x-ray pumping by coherently controlling the cooperative decay. First, we study an ideal case with purely superradiant decay and perfect control of the cooperative emission. A numerical analysis of x-ray pumping in nuclear forward scattering with coherent control of the cooperative decay via externally applied magnetic fields is presented. Next, we provide an extended survey of nuclei suitable for our scheme, and propose proof-of-principle implementations already possible with typical Mössbauer nuclear systems such as 57 Fe. Finally, we discuss the application of such control techniques to the population or depletion of long-lived nuclear states. PACS numbers: 73.20.Mf, 78.70.Ck, 75.78.Jp, 76.80.+y Coherent control in quantum optics and atomic physics provides an efficient tool to investigate atomic properties and favorably manipulate the dynamics of the system alike. Similar possibilities with nuclear systems have been considered with great interest [1-8] already shortly after the realization of the first laser in the optical band [9]. However, many quantum optical control schemes require the effective coupling of the driving field to the considered transition (Rabi frequency) to be of the same order as the relaxation rate of the same transition [10,11]. Consequently it is very demanding to exploit the direct laser driving of nuclear systems experimentally. Furthermore, the dream of the nuclear laser is at present equally out of reach. The pursuit of coherent sources for wavelengths around or below 1 nm is supported however by the advent and commissioning of x-ray free electron lasers [12,13], the availability of which will stimulate the transfer of quantum optical schemes to nuclei along these lines.A different route to coherent control of nuclear dynamics which does not rely on forthcoming x-ray light sources is coherent light scattering off nuclei in the low-excitation limit [14][15][16][17][18]. In particular, coherent nuclear forward scattering (NFS) is a routine technique experimentally studied in many labs around the world. In NFS, high-frequency light such as that from a synchrotron radiation (SR) source is monochromatized at a nuclear resonance energy, and then scatters coherently off a nuclear target. As has recently been realized, while being conceptionally different from the attempts to directly transfer quantum optical schemes to the nuclear realm, NFS does allow to explore coherent control of nuclei in experimental settings already available today [19][20][21][22]. The possibility of control exploited in these works ar...

show abstract

mentioning

confidence: 99%

Coherent control of the cooperative branching ratio for nuclear x-ray pumping

2011

Self Cite

View full text Add to dashboard Cite

show abstract

“…Using this scenario, the interaction of x-ray from the European X-ray Free Electron Laser (XFEL) [7] with nuclear two-level systems was studied theoretically [6,8]. The manipulation of nuclear state * Corresponding author.…”

Section: Introductionmentioning

confidence: 99%

Nuclear Coherent Population Transfer with X-Ray Laser Pulses

Liao

2013

Coherent Control of Nuclei and X-Rays

View full text Add to dashboard Cite

Coherent population transfer between nuclear states using x-ray laser pulses is studied. The laser pulses drive two nuclear transitions between three nuclear states in a setup reminding of stimulated Raman adiabatic passage used for atomic coherent population transfer. To compensate for the lack of γ-ray laser sources, we envisage accelerated nuclei interacting with two copropagating or crossed x-ray laser pulses. The parameter regime for nuclear coherent population transfer using fully coherent light generated by future X-Ray Free-Electron Laser facilities and moderate or strong acceleration of nuclei is determined. We find that the most promising case requires laser intensities of 10 17 -10 19 W/cm 2 for complete nuclear population transfer. As relevant application, the controlled pumping or release of energy stored in long-lived nuclear states is discussed. Keywords:isomer decay, gamma transitions and levels, nuclear quantum optics, x-ray and gamma-ray lasers Long-lived excited nuclear states, also known as isomers, can store large amounts of energy over longer periods of time. Isomer depletion, i.e., release on demand of the energy stored in the metastable state, has received great attention in the last one and a half decades, especially related to the fascinating prospects of nuclear batteries [1,2,3,4]. Depletion occurs when the isomer is excited to a higher level, which is associated with freely radiating states and therefore releases the energy of the metastable state. Coherent population transfer between nuclear states would therefore not only be a powerful tool for preparation and detection in nuclear physics, but also especially useful for control of energy stored in isomers.In atomic physics, a successful and robust way for atomic coherent population transfer is the stimulated Raman adiabatic passage (STIRAP) [5], a technique in which two coherent fields couple to a three-level system. The transfer of such schemes to nuclear systems, although encouraged by progress of laser technology, has not been accomplished due to the lack of γ-ray laser sources. The pursuit of coherent sources for wavelengths around or below 1 Å is supported however by the advent and commissioning of x-ray free electron lasers, the availability of which will stimulate the transfer of quantum optical schemes to nuclei.To bridge the gap between x-ray laser frequency and nuclear transition energies, a key proposal is to combine moderately accelerated target nuclei and novel x-ray lasers [6]. Using this scenario, the interaction of x-ray from the European X-ray Free Electron Laser (XFEL) [7] with nuclear two-level systems was studied theoretically [6,8]. The manipulation of nuclear state * Corresponding author. Tel.: +49(0)6221 516162, fax: +49 (0)6221 516152 Email addresses: Wen-Te.Liao@mpi-hd.mpg.de (Wen-Te Liao), Palffy@mpi-hd.mpg.de (Adriana Pálffy ), Keitel@mpi-hd.mpg.de (Christoph H. Keitel) population by STIRAP and the coherent control of isomers have however never been addressed, partially because of the poor coh...

show abstract

“…(2), ∆ B denotes the Zeeman energy shift of the nuclear transitions proportional to the magnetic field B. Furthermore, a 31 = a 42 = a = 2/3 is the corresponding Clebsch-Gordan coefficient [15,43,48] for the ∆m = 0 transitions. The parameter η is defined as η = 6Γ L ξ, where Γ = 1/141.1 GHz is the γ-decay rate of excited states, ξ represents the effective resonant thickness [42][43][44] and L = 10 µm the thickness of the target, respectively.…”

mentioning

confidence: 99%

“…The parameter η is defined as η = 6Γ L ξ, where Γ = 1/141.1 GHz is the γ-decay rate of excited states, ξ represents the effective resonant thickness [42][43][44] and L = 10 µm the thickness of the target, respectively. Further notations are c the speed of light and Ω F (B) for the forward (backward) Rabi frequency which is proportional to the electric field E of the x-ray pulse [47,48]. The forward scattered x rays are treated as incident field for the backward scattering, i.e.,…”

mentioning

confidence: 99%

See 1 more Smart Citation

Proposed Entanglement of X-ray Nuclear Polaritons as a Potential Method for Probing Matter at the Subatomic Scale

Liao

Pálffy

2014

Phys. Rev. Lett.

Self Cite

View full text Add to dashboard Cite

A setup for generating the special superposition of a simultaneously forward-and backward-propagating collective excitation in a nuclear sample is studied. We show that by actively manipulating the scattering channels of single x-ray quanta with the help of a normal incidence x-ray mirror, a nuclear polariton which propagates in two opposite directions can be generated. The two counterpropagating polariton branches are entangled by a single x-ray photon. The quantum nature of the nuclear excitation entanglement gives rise to a subangstromwavelength standing wave excitation pattern that can be used as a flexible tool to probe matter dynamically on the subatomic scale. PACS numbers: 78.70.Ck, 03.67.Bg, 42.50.Nn, 76.80.+y Keywords: x-ray quantum optics, entanglement, interference effects, nuclear forward scattering Optical lasers have been at the heart of quantum physics for the last decades. The commissioning of the first x-ray free electron lasers (XFEL) [1][2][3][4][5] and the developments of x-ray optics elements [6][7][8][9][10][11][12] bring into play higher photon frequencies and promote the emerging field of x-ray quantum optics [13]. Apart from a powerful imaging tool, coherent x-ray light may also offer a solution for avoiding the diffraction limit bottleneck for compact photonic devices [14,15], and render possible the coherent control of transitions in ions [16][17][18][19][20] and nuclei [21][22][23][24][25][26][27]. Furthermore, new x-ray optical elements such as beam splitters [12] and mirrors [9,10] lay the foundation for developing quantum interferometers and controlling the quantum behavior of single x-ray photons. Apart from their potential in the field of quantum information [28,29], the probing proficiency of single x-ray quanta would be an appreciated counterpart to traditional x-ray imaging techniques with intense x-ray beams [30].In this Letter we present a coherent control scheme that exploits the quantum properties of a single x-ray photon to generate nuclear polariton entanglement and a subangstromwavelength standing wave excitation pattern. The key for our setup is a special superposition of a simultaneously forwardand backward-propagating collective excitation in a nuclear sample. The system comprising a single x-ray photon resonantly propagating through a sample of 57 Fe Mössbauer nuclei forms a nuclear polariton [31][32][33][34]. We show how with the help of a normal incidence x-ray mirror [10], this polariton can be split in two entangled counterpropagating branches that share the same single photon. By actively distributing the single-photon wave packet in a controlled way, both the symmetric and the antisymmetric versions of polariton entanglement can be achieved. This leads to the creation of a standingwave nuclear excitation pattern with subangstrom-wavelength in the absence of any x-ray cavity or Bragg condition in the sample. In conjunction with phonon excitation, this standing wave can be used to dynamically probe the sample lattice using a single x-ray photon.The underlying p...

show abstract

Electric-dipole-forbidden nuclear transitions driven by super-intense laser fields

Cited by 58 publications

References 49 publications

Coherent control of the cooperative branching ratio for nuclear x-ray pumping

Coherent control of the cooperative branching ratio for nuclear x-ray pumping

Nuclear Coherent Population Transfer with X-Ray Laser Pulses

Proposed Entanglement of X-ray Nuclear Polaritons as a Potential Method for Probing Matter at the Subatomic Scale

Contact Info

Product

Resources

About