Next generation cryogenic trap XII I XI X II HCI clocks III - - PowerPoint PPT Presentation

▶
next generation cryogenic trap
SMART_READER_LITE
LIVE PREVIEW

Next generation cryogenic trap XII I XI X II HCI clocks III - - PowerPoint PPT Presentation

Feb 14, 2024 161 likes •667 views

Next generation cryogenic trap XII I XI X II HCI clocks III IX IIII VIII V VII Jos R. Crespo Lpez-Urrutia VI Max-Planck-Institut fr Kernphysik Table-top EBITs for PTB, Petra-III, Blaum division HCI-clock laboratory at PTB

slide-1
SLIDE 1

Next generation cryogenic trap

slide-2
SLIDE 2

José R. Crespo López-Urrutia Max-Planck-Institut für Kernphysik

HCI clocks

XII I II III IIII V VI VII VIII IX X XI

slide-3
SLIDE 3

Table-top EBITs for PTB, Petra-III, Blaum division

slide-4
SLIDE 4

HCI-clock laboratory at PTB

slide-5
SLIDE 5

New MPIK-PTB cryogenic trap in operation

  • First device shipped to PTB, now operating
  • Week-long ion storage time
  • Ultra-low vibrations
  • Electric and magnetic shielding improved
slide-6
SLIDE 6

Piet Schmidt Tobias Leopold Peter Micke Steven King + Lukas Spieß

Frequency metrology group at PTB

slide-7
SLIDE 7

Sympathetic resolved-sideband cooling

slide-8
SLIDE 8

Quantum-logic spectroscopy on Ar13+

slide-9
SLIDE 9

Ar13+ Zeeman structure

‐factors from [Agababaev et al. arXiv:1812.06431]

Landé ‐factors Dirac Dirac + interactions Dirac + interactions + QED

 measurement of ground‐ and excited state g‐factors with <10 ppm  future: optical clock operation, isotope shifts, …

slide-10
SLIDE 10

History of Ar13+ frequency measurements

new Penning trap measurement [S. Sturm et al. (MPIK), to be published]

  • ur current resolution:

~5 Hz

2P1/2 2P3/2

441 nm Ar13+ future

slide-11
SLIDE 11

Quantum-logic spectroscopy on Ar13+

slide-12
SLIDE 12

State of the art: systematic uncertainty

1E‐19 1E‐18 1E‐17 1E‐16 1E‐15 1E‐14 1E‐13 1E‐12 1E‐11 1E‐10 1E‐09 1950 1960 1970 1980 1990 2000 2010 2020 (estimated) systematic uncertainty year Cs clocks

  • ptical clocks

HCI spectroscopy

slide-13
SLIDE 13

Frequency standards for VUV: Examples of forbidden transitions

slide-14
SLIDE 14

M3 decay of Xe26+ (Ni-like) 129,132Xe

  • E. Träbert, P. Beiersdorfer, and G. V. Brown, Phys. Rev. Lett. 98

98, 263001 (2007)

LLNL X-ray microcalorimeter observation:

  • Transition energy: 1450 eV
  • Lifetime (15.06±0.24) ms
  • Q-value

5 1015

slide-15
SLIDE 15

47,49Ti18+

E = 28.352 eV  = 43.7 nm Q = 1.3 × 1016

Hyperfine-induced lifetime  1 s Measured: 1.8 s (S. Schippers)

57Fe22+

E = 43.169 eV τ = 20 s  = 28.72 nm Q = 2.2 × 1017 33S12+ E = 24.695 eV τ = 10 s  = 50.21 nm Q=6 × 1015

1s22s2p 3P0 - 1s22s2 1S0 Beryllium-like isoelectronic sequence

slide-16
SLIDE 16

78 80 82 84 86 88 90 92 94 96 98 100 102 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030

Atomic number Z

10 20 30 40 50 60

Q‐value for 4f135s‐4f14 transition Wavelength (nm)

Example: Nd-like isoelectronic sequence

Magnetic octupole VUV decays are very slow

=10 nm

Q value 3×1023

=40 nm

Q value 1028

slide-17
SLIDE 17
  • Use HHG as light source for spectroscopy in XUV
  • Coherently transfer all comb modes from IR to XUV
  • Perform direct frequency comb spectroscopy (DIFCOS)

High-harmonic generation at 100 MHz

A Cingöz et al. Nature 482, 68-71 (2012)

  • R. Jason Jones et al. Phys. Rev. Lett. 94, 193201 (2005)
  • Challenge: Obtain enough intensity in XUV

→ use enhancement cavity Experiment by Janko Nauta, MPIK

slide-18
SLIDE 18

The three-step model

  • Ionized electrons do not immediately leave their

nuclei

  • Significant probability of electron returning to nucleus
  • Three steps:
  • 1. Tunnel ionization in laser electric field
  • 2. Acceleration of quasi-free electron in laser field
  • 3. Recollision can lead to
  • recombination to ground state: emission of HHG-photons
  • elastic scattering: Above-threshold ionization
  • inelastic scattering: double ionization
slide-19
SLIDE 19

High harmonic generation (HHG)

Tunneling (I  1014 ... 1015 W/cm2 ) Recollision and recombination

  • max. 3.17 Up

Up = I/4w2

Ponderomotive potential

Ip

slide-20
SLIDE 20

Why is the radiation harmonic?

Photon picture

1 2    q n n

FUN HHG

 

E (t)

t

  • Wave dynamics: Emission of specific harmonics 2x per cycle
  • Due to target isotropy => Not valid in few-cycle pulses!
  • At the collision all possible harmonics are generated
  • This process is periodic: Fourier transform yields harmonics
slide-21
SLIDE 21

General Setup for HHG

  • Differential pumping needed
  • Long-term stability of enhancement resonator mirrors requires

excellent vacuum

  • UHV setup needed

Small tub Small tube with with noble gas noble gas (tar (target) t) fund fundamen amenta tal l wavelength length harmonics harmonics

slide-22
SLIDE 22

Image adapted from R. Jason Jones, University of Arizona

(JILA) R. J. Jones et. al., PRL 94 94, 193201 (2005) (MPQ) C. Gohle et. al., Nature 436 436, 234 (2005)

Intracavity high-harmonic generation

slide-23
SLIDE 23

VUV frquency comb and HCI

  • In-vacuo enhancement cavity
  • In 15 μm focus:  1013 W/cm2
  • 100 MHz repetition rate

EBIT Decceleration RF linear trap VUV frequency comb

slide-24
SLIDE 24

Design of HHG focus

Focus waist  15 μm With 10 W frequency comb Enhancement to  1013 W/cm2 High-harmonics beams cylindrical incoupling mirror compensating astigmatism around focus region

slide-25
SLIDE 25

Vibration suppression

  • Enhancement cavity mounted
  • n high-stiffness titanium frame
  • n optical table
  • Pump vibrations absorbed

through mechanical low-pass filter, factor 10 reduction in amplitude

slide-26
SLIDE 26

Temperature-controlled container for HHG-frequency comb

slide-27
SLIDE 27

Modern slavery…

slide-28
SLIDE 28
slide-29
SLIDE 29
  • For resonant enhancement, the length of the five-mirror ring-

cavity is locked to the repetition rate of the frequency comb

  • Maximum enhancement of 100-200 is reached for exactly

matched cavity lengths

HHG in gas jet with differential pumping

slide-30
SLIDE 30

Our first multi-photon test: Velocity-map imaging at 100 MHz repetition rate

slide-31
SLIDE 31

With enhancement cavity locked, multiphoton ionization of gas atoms and molecules takes place at the focus (Janko Nauta et al.)

Multi-photon ionization in focus

  • Multi-photon above-threshold

ionization arises at similar intensities as high-harmonic generation

  • Fundamental IR at 1.2 eV
  • Velocity-map imaging of Xe, Kr,

Ar with ionization potentials up to 15.6 eV

  • 16-photon signal observed
  • Horizontal and vertical laser

polarization possible using intra- cavity waveplates

slide-32
SLIDE 32

Polarization side-on

With enhancement cavity locked on frequency comb, above-threshold multiphoton ionization of Xe atoms takes place at the focus with 2.5×1012 W/cm2

(Janko Nauta, Jan-Hendrik Oelmann, Alexander Ackermann, MPIK)

slide-33
SLIDE 33

Next step: HHG differentially pumped jet

slide-34
SLIDE 34

HHG in gas jet with differential pumping

(Janko Nauta, Ronja Pappenberger, Jan-Hendrik Oelmann, MPIK)

slide-35
SLIDE 35

What the PI wanted

Triple differential pumping system for HHG gas nozzle

nozzle skimmers skimmer 1st 2nd 3rd laser

(Janko Nauta, Ronja Pappenberger, Jan-Hendrik Oelmann, MPIK)

slide-36
SLIDE 36

Next generation cryogenic trap

  • Cryogenic, XUHV
  • Ultra-low vibration
  • Superconducting high-Q RF resonator

(Julian Stark, Christian Warnecke, Steffen Kühn, Michael Rosner

slide-37
SLIDE 37
  • Whole new class of laser-accessible targets
  • Low sensitivity to DC and AC Stark shifts
  • Forbidden transitions suitable as frequency

standards

  • High sensitivity to fine-structure constant
  • Large QED load
  • Optical transitions arising from, e. g.:
  • Fine structure in Be-like, B-like ions
  • HFS of ground state in H-like ions:

Ho66+, Re74+, Tl80+, Pb81+, Bi82+

Advantages for fundamental studies

slide-38
SLIDE 38

Summary

  • HCI are ultra-stable, universal and reproducible probes of

fundamental physics; effects magnified by Z-scaling laws

  • QED, relativistic as well as nuclear interactions and few-

electron correlations in “tunable” admixtures

  • Whole new class of laser-accessible targets, with Z and

ionic charge as parameters

  • Great variety of optical and EUV lines, fine and hyperfine

transitions up to the highest charge states

  • Stable up to X-ray region
  • HCI frequency metrology enabled by sympathetic cooling,

forbidden transitions suitable as frequency standards

  • Optical clocks for studies of α variation, Lorentz

invariance benefit from insensitivity of HCI to perturbations

slide-39
SLIDE 39

Strong overlap of electronic and nuclear wavefunctions

slide-40
SLIDE 40

Precision Isotope Shift Measurements in Calcium Ions Using Quantum Logic Detection Schemes

Florian Gebert, Yong Wan, Fabian Wolf, Christopher N. Angstmann, Julian C. Berengut, and Piet O. Schmidt, Phys. Rev. Lett. 115, 053003 (2015)

Precision isotope shifts

slide-41
SLIDE 41

Probing New Long-Range Interactions by Isotope Shift Spectroscopy

Julian C. Berengut, Dmitry Budker, Cédric Delaunay, Victor V. Flambaum, Claudia Frugiuele, Elina Fuchs, Christophe Grojean, Roni Harnik, Roee Ozeri, Gilad Perez, and Yotam Soreq

  • Phys. Rev. Lett. 120, 091801 (2018)

Probing new spin-independent interactions through precision spectroscopy in atoms with few electrons

Cédric Delaunay, Claudia Frugiuele, Elina Fuchs, and Yotam Soreq

  • Phys. Rev. D 96, 115002 (2017)

Precision isotope shifts

slide-42
SLIDE 42

10‐15 10‐14 10‐13 10‐12 10‐11 10‐10 10‐9

10‐20 10‐19 10‐18 10‐17 10‐16 10‐15 10‐14 10‐13 10‐12 10‐11 10‐10 10‐9 10‐8 10‐7 10‐6 10‐5 10‐4 10‐3 10‐2 10‐1 100 101

nucleus

Ca15+ P2+Q2 Radius (m) Ca+

Comparison of electron density

Even in light elements, in HCI the electron-nucleus

  • verlap is enhanced by two orders of magnitude
slide-43
SLIDE 43

10‐16 10‐15 10‐14 10‐13 10‐12 10‐11 10‐10 10‐9

10‐20 10‐18 10‐16 10‐14 10‐12 10‐10 10‐8 10‐6 10‐4 10‐2 100 102

CaIIK1‐1 CaIIK2+1 CaIIK2‐1 CaIIK2‐2 CaIIK3+1 CaIIK3+2 CaIIK3‐1 CaIIK3‐2 CaIIK3‐3 CaIIK4+1 CaIIK4+2 CaIIK4+3 CaIIK4‐1 CaIIK4‐2 CaIIK4‐3 CaIIK4‐4 Yukawa‐1 1‐1 2‐1 3‐1 4‐1

P2+Q2 Radius (m)

Comparison of electron density

Hypothetical Yukawa particles in the nucleus affect the outer electron (isotopic shifts) far more strongly in Ca15+ than in Ca+

Yukawa particle

slide-44
SLIDE 44

Coupling to the nuclear clock in the VUV

slide-45
SLIDE 45

Electron with Ek = 8 eV has a de Broglie wavelength of 0.434 nm

Coupling free electron-nucleus

slide-46
SLIDE 46

Photon-assisted bridge

Internal conversion from excited electronic states of 229Th ions Pavlo V. Bilous, Georgy A. Kazakov, Iain D. Moore, Thorsten Schumm, and Adriana Pálffy

  • Phys. Rev. A 95, 032503 (2017)
slide-47
SLIDE 47

Photon-assisted bridge

Internal conversion from excited electronic states of 229Th ions Pavlo V. Bilous, Georgy A. Kazakov, Iain D. Moore, Thorsten Schumm, and Adriana Pálffy

  • Phys. Rev. A 95, 032503 (2017)
slide-48
SLIDE 48

Photon-assisted bridge

From: P. Bilous & A. Palffy, 2018

slide-49
SLIDE 49

MPIK: J. Nauta, J.-H. Oelmann, J. Stark, C. Warnecke, S. Bogen, S. Kühn, M. K. Rosner, L. Schmöger, O. O. Versolato, M. Schwarz, A. Windberger, H. Bekker, A. Borodin, P. Micke, L. Spiess, F. Brunner, JRCLU, T. Pfeifer PTB: P. Micke, T. Leopold, S. King, L. Spiess, M. Kohnen, J. Ullrich, P. O. Schmidt UNSW: J. Berengut Delaware: M. Safronova Aarhus University: M. Drewsen

slide-50
SLIDE 50

MPIK EBIT team