Shaping the spectrum of entangled photons M Hendrych
- Slides: 32
Shaping the spectrum of entangled photons M. Hendrych, A. Valencia, M. Mičuda, Xiaojuan Shi, Payam Abolghasem, Amr Helmy, and J. P. Torres ICFO – Institute of Photonic Sciences Barcelona
Quantum Optical Applications • Quantum computing – Quantum computer (calculations, database lookup, etc. ) – Material design, simulations • Quantum cryptography • Quantum random-number generation • Quantum metrology – Clock synchronization – Quantum optical coherence tomography – Squeezed states (grav. waves, magnetometers) • Quantum lithography (NOON states) • Quantum lawn-mowers
Outline • What we do – Frequency correlations of entangled photon pairs – Bandwidth control – Waveform shaping • How we do it – Tailoring group velocities by pulse-front tilt (angular dispersion) – Tailoring momentum-frequency entanglement using noncollinear geometries (spatial-to-spectral mapping) • Uof. T/ICFO collaboration – Design waveguides with suitable dispersive properties
• Anticorrelated • Correlated Types of correlations • Uncorrelated
Applications • Anticorrelated – Clock synchronization (A. Valencia et al. , Appl. Phys. Lett 85 , 2655 (2004)) – Dispersion compensation (even orders) (J. D. Franson, Phys. Rev. A 45, 3126 (1992)) • Correlated – Clock synchronization and position measurement (V. Giovannetti et al. , Nature 412, 417 (2001)) – Dispersion compensation (all orders) • Uncorrelated – Heralded single photons (pure state)
Bandwidth control
Bandwidth control • Generation of ultrashort biphotons M. Hendrych et al. , ar. Xive quant-ph/0807. 4063 • Broad bandwidth in OCT S. Carrasco et al. , Opt. Lett. 29, 2429 (2004) – increases axial resolution of imaging • Quantum illumination S. Lloyd, Science 321, 1463 (2008) – Increases efficiency of detecting an object by 2 m, m is Nasr number bits. Rev. of Lett. entanglement et al. , of Phys. 100, 183601 (2008)
Waveform shaping
Spontaneous parametric downconversion State of SPDC photons Nonlinear crystal Joint spectrum Phase mismatch
How to tailor the biphoton’s spectrum? By controlling – group velocities – group velocity dispersion – spatial shape of the pump beam • Search for material and wavelengths with suitable properties (Oxford, MIT) ? ? ? MIT desing, ne search. * • Design materials using quasi phase-matching and chirped * (Boston, Stanford, Barcelona) • Phase matching using Bragg-reflection waveguides (Toronto) • Pulse-front tilt (Barcelona) • Noncollinear geometries (Barcelona)
Pulse-front tilt y Effective group velocity dispersion
Experimental setup SHG - second harmonic generation, M - mirrors, G - gratings, PBS - polarizing beamsplitter, Mono - monochromators, D - detectors, & - counter and coincidence electronics.
Joint spectrum BBO: type II, 2 mm Theory Experiment
Joint spectrum – anticorrelated Theory Experiment
Joint spectrum – uncorrelated Theory Experiment
Joint spectrum – correlated Theory Experiment
Frequency correlations in HOM M. Hendrych et al. , Opt. Lett. 32, 2339 (2007)
Bandwidth control Singles Coincidences M. Hendrych et al. , ar. Xive quant-ph/0807. 4063 PRA *
Bandwidth Control with Chirped Quasi-Phase Matching Collaboration with Boston & Stanford Univs. NORMALIZED INTENSITY S. Carrasco et al. , Opt. Lett. 29, 2429 (2004) M. Nasr et al. , Phys. Rev. Lett. 100, 183601 (2008)
Spatial-to-spectral mapping S. Carrasco et al. , PRA 70, 043817 (2004)
Spatial-to-spectral mapping Space Joint spectrum Citace teorie Silvia? *
Spatial-to-spectral mapping Joint spectrum along the antidiagonal Idler wavelength Image of spatial mode of the pump A. Valencia et al. , Phys. Rev. Lett. 99, 243601 (2007) Signal wavelength
Modifying the frequency correlations via spatial-to-spectral mapping
Combining pulse-front tilt and spatial-to-spectral mapping X. Shi et al. , Opt. Lett. 33, 875 (2008)
Collaboration with Uof. T Amr Helmy Payam Abolghasem Goal: Design Bragg-reflection waveguides to produce 1) entangled photons with desired bandwidth 2) frequency-uncorrelated biphotons
Bragg-reflection waveguides (BRW) - Al. Ga. As structure - Design of the structure allows controlling dispersive properties
Compound semiconductors Alx. Ga 1 -x. As – mature fabrication technology – large transparency window – large nonlinear coefficient – large damage threshold – monolithic integration • cost effectiveness • small device size • portable devices • low power consumption • reliable performance
Phase-matching and GVD control with BR waveguides
Joint spectrum w/ BR waveguides Type I for different ridge widths W
Joint spectrum w/ BR waveguides Type II Dl = 670 nm Dl = 20 nm Dl = 134 nm W = 725 nm lp = 752 nm L = 1 mm W = 2500 nm lp = 775 nm L = 1 mm
Summary • Frequency correlations: Thank you!!! • Bandwidth: • Waveform: • Fabricate waveguides and measure their properties
- Facts about photons
- Quantum imaging with undetected photons
- Single photon detector
- Do photons have momentum
- Energy planck's constant
- Implications of quantum entanglement
- Don't be entangled with the affairs of this world
- Orbital diagram for cu
- Absortpion
- Phản ứng thế ankan
- Môn thể thao bắt đầu bằng chữ f
- Voi kéo gỗ như thế nào
- Thiếu nhi thế giới liên hoan
- Sự nuôi và dạy con của hươu
- điện thế nghỉ
- Biện pháp chống mỏi cơ
- Một số thể thơ truyền thống
- Trời xanh đây là của chúng ta thể thơ
- Số nguyên tố là số gì
- Phối cảnh
- Các châu lục và đại dương trên thế giới
- Thế nào là hệ số cao nhất
- Tư thế worms-breton
- Hệ hô hấp
- Tư thế ngồi viết
- đặc điểm cơ thể của người tối cổ
- Cái miệng nó xinh thế chỉ nói điều hay thôi
- Cách giải mật thư tọa độ
- Bổ thể
- ưu thế lai là gì
- Tư thế ngồi viết
- Thẻ vin