Dr. Guy Matmon

Guy Matmon is a tenure-track scientist in the Quantum Technologies Group. His degrees include a BSc in physics and mathematics and a MSc in applied physics from the Hebrew University in Jerusalem, and a PhD at the Cavendish Laboratory at Cambridge University. After obtaining an undergraduate degree he spent several years in Industry, in an optical communications company, Chiaro Networks, developing all optical high-capacity routers. After his PhD he moved to the London Centre for Nanotechnology at University College London, where he worked on optical control of single donors in silicon and of rare-earth-doped insulators. He has done various consulting work on infrared spectroscopy and optical manufacturing processes, and is the coinventor of twenty eight patents.

Management of the IR beam line (X01DC) at the Swiss Light Source SLS, management of the optical laboratory at the LMN, supervision of QT PhD students.

Quantum coherent control of single and double donors in silicon, magneto-optical control of rare-earth doped fluorides, THz quantum cascade lasers, Si/SiGe heterostructures, doped-silicon based THz sources, GaAs/AlGaAs near infrared phase modulators, optical switching.

For an extensive overview we kindly refer you to our publication repository DORA

Viral Lasers for Biological Detection, John E. Hales, Guy Matmon, Paul A. Dalby, John M. Ward and Gabriel Aeppli, Nature Communications volume 10, Article number: 3594 (2019)  The polymerase chain reaction (PCR) underpins much of biomedical detection because of both its remarkable chemical amplification and specificity as well as the ubiquity of genetic material. There is no equivalent technique for detecting particular proteins, meaning that immunoassays are much less powerful. We show here that by using a viral chromophore in solution as a lasing medium, new types of biomedical assays become possible. In particular, a viral load measurement and a mix-and-measure immunoassay (detecting a phage antibody) are demonstrated, both with sensitivities orders of magnitude beyond what can be achieved with conventional fluorescence. Additionally, the on-off character of lasing can be exploited for digital medicine.

Metrology of complex refractive index for solids in the terahertz regime using frequency domain spectroscopy, Chick, S. R., Murdin, B. N., Matmon, G., Naftaly, M., Metrologia volume 55(6), p. 771 (October 2018) Frequency domain spectroscopy allows an experimenter to establish optical properties of solids in a wide frequency band including the technically challenging 10 THz region, and in other bands enabling metrological comparison between competing techniques. We advance a method for extracting the optical properties of high-index solids using only transmission-mode frequency domain spectroscopy of plane-parallel Fabry–Perot optical flats. We show that different data processing techniques yield different kinds of systematic error, and that some commonly used techniques have inherent systematic errors which are underappreciated. We use model datasets to cross-compare algorithms in isolation from experimental errors, and propose a new algorithm which has qualitatively different systematic errors to its competitors. We show that our proposal is more robust to experimental non-idealities such as noise or apodization, and extract the complex refractive index spectrum of crystalline silicon as a practical example. Finally, we advance the idea that algorithms are complementary rather than competitive, and should be used together as part of a toolbox for better metrology.

Two- to three-dimensional crossover in a dense electron liquid in silicon, G. Matmon, E. Ginossar, B. J. Villis, A. Kölker, T. Lim, H. Solanki, S. R. Schofield, N. J. Curson, J. Li, B. N. Murdin, A. J. Fisher, G. Aeppli. Physical Review B volume 97(15), p. 5306 (April 2018), Doping of silicon via phosphine exposures alternating with molecular beam epitaxy overgrowth is a path to Si:P substrates for conventional microelectronics and quantum information technologies. The technique also provides a well-controlled material for systematic studies of two-dimensional lattices with a half-filled band. We show here that for a dense (n_s = 2.8×10¹⁴ cm⁻²) disordered two-dimensional array of P atoms, the full field magnitude and angle-dependent magnetotransport is remarkably well described by classic weak localization theory with no corrections due to interaction. The two- to three-dimensional crossover seen upon warming can also be interpreted using scaling concepts developed for anistropic three-dimensional materials, which work remarkably except when the applied fields are nearly parallel to the conducting planes.

Coherent superpositions of three states for phosphorous donors in silicon prepared using THz radiation, Chick S., Stavrias N., Saeedi K., Redlich B., Greenland P. T., Matmon G., Naftaly M., Pidgeon C. R., Aeppli G., Murdin B. N. Nature Communications volume 8, p. 16038 (July 2017), Superposition of orbital eigenstates is crucial to quantum technology utilizing atoms, such as atomic clocks and quantum computers, and control over the interaction between atoms and their neighbours is an essential ingredient for both gating and readout. The simplest coherent wavefunction control uses a two-eigenstate admixture, but more control over the spatial distribution of the wavefunction can be obtained by increasing the number of states in the wavepacket. Here we demonstrate THz laser pulse control of Si:P orbitals using multiple orbital state admixtures, observing beat patterns produced by Zeeman splitting. The beats are an observable signature of the ability to control the path of the electron, which implies we can now control the strength and duration of the interaction of the atom with different neighbours. This could simplify surface code networks which require spatially controlled interaction between atoms, and we propose an architecture that might take advantage of this.

Optical response from terahertz to visible light of electronuclear transitions in LiYF₄:Ho³⁺, G. Matmon, S. A. Lynch, T. F. Rosenbaum, A. J. Fisher and G. Aeppli, Physical Review B volume 94(20), p. 5132 (November 2016). Because of its role as a model system with tunable quantum fluctuations and quenched disorder, and the desire
for optical control and readout of its states, we have used high-resolution optical absorption spectroscopy to measure the crystal-field excitations for Ho³⁺ ions in LiHo_xY_1−xF₄ from the terahertz to visible regimes. We show that many of the excitations yield very narrow lines visibly split even by the nuclear hyperfine interaction, making Ho3+ in LiHo_xY_1−xF₄ a candidate host for optically addressable electronuclear qubits with quality factors
as high as Q = 4.7×10⁵, where the higher-lying levels are electronic singlets. Optical transitions in the easily accessible near- and mid-infrared are narrow enough to allow readout of the ground-state electronuclear qubits responsible for the interesting magnetism of LiHo_xY_1−xF₄. While many of the higher-lying states have been observed previously, we also report here detailed spectra of terahertz excitations. The strengths of the electric
and magnetic dipole crystal-field transition lines of five of the lowest excited spin-orbit manifolds of dilute LiYF4:Ho3+ were calculated and compared with measurement. The magnitude of the nuclear hyperfine coupling was used to assign the correct upper and lower states to transition lines.

Quantitative analysis of electrically detected Ramsey fringes in P-doped Si, P. T. Greenland, G. Matmon, B. J. Villis, E. T. Bowyer, J. Li, B. N. Murdin, A. F. G. van der Meer, B. Redlich, C. R. Pidgeon and G. Aeppli, Physical Review B volume 92(16), p. 5310 (October 2015), This work describes detection of the laser preparation and subsequent coherent manipulation of the quantum states of orbital levels of donors in doped Si, by measuring the voltage drop across an irradiated Si sample. This electrical signal, which arises from thermal ionization of excited orbital states, and which is detected on a millisecond time scale by a voltmeter, leads to much more sensitive detection than can be had using optical methods, but has not before been quantitatively described from first principles. We present here a unified theory which relates the voltage drop across the sample to the wave function of the excited donors, and compare its predictions to experiments in which pairs of picosecond pulses from the Dutch free-electron laser FELIX are used to resonantly and coherently excite P donors in Si. Although the voltage drop varies on a millisecond time scale we are able to measure Ramsey oscillation of the excitation on a picosecond time scale, thus confirming that the donor wave function, and not just its excited state population, is crucial in determining the electrical signal. We are also able to extract the recombination rate coefficient to the ground state of the donor as well as the photoionization cross section of the excited state and phonon induced thermal ionization rate from the excited state. These quantities, which were previously of limited interest, are here shown to be important in the description of electrical detection, which, in our unoptimized configuration, is sensitive enough to enable us to detect the excitation of ∼10⁷ donors.

Broadband Terahertz Metamaterial Absorber Based on Asymmetric Resonators With Perfect Absorption
Yongzheng Wen, Wei Ma, Joe Bailey, Guy Matmon and Xiaomei Yu, IEEE Transactions on Terahertz Science and Technology}, (May 2015), In this paper, a broadband terahertz (THz) metamaterial absorber using asymmetric split ring resonator (ASR) was designed, fabricated, and characterized. By breaking the symmetry of a split ring resonator, two asymmetric resonances are excited from a dipole resonance, which enhance both the absorption and Q-factor. With the integration of four different ASRs into one unit cell, a broadband absorber experimentally obtained a 0.82-THz bandwidth with absorptivity of more than 0.9, which is 3.4 times as wide as the 0.24-THz bandwidth of the symmetric dipole peak. The proposed broadband absorber has great application potentials in the THz spectroscopy, imaging, and sensing.

Coherent creation and destruction of orbital wavepackets in Si:P with electrical and optical read-out, K. L. Litvinenko, E. T. Bowyer, P. T. Greenland, N. Stavrias, Juerong Li, R. Gwilliam, B. J. Villis, G. Matmon, M. L. Y. Pang, B. Redlich, A. F. G. van der Meer, C. R. Pidgeon, G. Aeppli and B. N. Murdin. Nature Communications volume 6, p. 6549 (March 2015), The ability to control dynamics of quantum states by optical interference, and subsequent
electrical read-out, is crucial for solid state quantum technologies. Ramsey interference has been successfully observed for spins in silicon and nitrogen vacancy centres in diamond, and for orbital motion in InAs quantum dots. Here we demonstrate terahertz optical excitation, manipulation and destruction via Ramsey interference of orbital wavepackets in Si:P with electrical read-out. We show milliradian control over the wavefunction phase for the two-level system formed by the 1s and 2p states. The results have been verified by all-optical echo detection methods, sensitive only to coherent excitations in the sample. The experiments open a route to exploitation of donors in silicon for atom trap physics, with concomitant potential for quantum computing schemes, which rely on orbital superpositions to, for example, gate the magnetic exchange interactions between impurities.

Absorption modulation of terahertz metamaterial by varying the conductivity of ground plane
Yongzheng Wen, Wei Ma, J. Bailey, G. Matmon, G. Aeppli and Xiaomei Yu. Applied Physics Letters, 105(14), p. 141111 (10/2014).

Planar broadband and high absorption metamaterial using single nested resonator at terahertz frequencies
Yongzheng Wen, Wei Ma, J. Bailey, G. Matmon, Xiaomei Yu and G. Aeppli. Optics Letters,39(6), pp. 1589-92 (03/2014).

Picosecond dynamics of a silicon donor based terahertz detector device
E. T. Bowyer, B. J. Villis, J. Li, K. L. Litvinenko, B. N. Murdin, M. Erfani, G. Matmon, G. Aeppli, J.-M. Ortega, R. Prazeres, L. Dong, Xiaomei Yu. Applied Physics Letters, 105(2), p. 021107 (01/2014).

Polarization-independent dual-band terahertz metamaterial absorbers based on gold/parylene-C/silicide structure
Yongzheng Wen, Wei Ma, J. Bailey, G. Matmon, Xiaomei Yu and G. Aeppli. Applied Optics, 52(19), pp.4536-4540 (07/2013).

Inhomogeneous broadening of phosphorus donor lines in the far-infrared spectra of single-crystalline SiGe
S. A. Lynch, G. Matmon, S. G. Pavlov, K. L. Litvinenko, B. Redlich, A. F. G. van der Meer, N. V. Abrosimov, and H.-W. Hübers. Physical Review B, 82(24), pp. 5206--5212, December 2010.

Si/SiGe quantum cascade superlattice designs for terahertz emission
G. Matmon, D. J. Paul, L. Lever, M. Califano, Z. Ikonić, R. W. Kelsall, J. Zhang, D. Chrastina, G. Isella, H. von Känel, E. Müller, and A. Neels. Journal of Applied Physics}, 107(5), pp. 3109--3115, 2010.

Si/SiGe bound-to-continuum quantum cascade terahertz emitters
D. J. Paul, G. Matmon, L. Lever, Z. Ikonic, R. W. Kelsall, D. Chrastina, G. Isella, H. von Känel. Proceedings of the SPIE, Vol 6996, Silicon Photonics and Photonic Integrated Circuits, 69961C (1 May 2008).

A Review of Progress Towards Terahertz Si/SiGe Quantum Cascade Lasers
D. J. Paul, P. Townsend, G. Matmon, Z. Suet, R. W. Kelsall, Z. Ikonic, P. Harrison, J. Zhang, D. J. Norris, A. G. Cullis, C. R. Pidgeon, P. Murzyn, B. Murdin, M. Bain, H. S. Gamble, M. Zhao, and W.-X. Ni. IETE Journal of Research, 53(3), pp. 285-292, May-June 2007.

Toward silicon-based lasers for terahertz sources
S. A. Lynch, D. J. Paul, P. Townsend, G. Matmon, Z. Suet, R. W. Kelsall, Z. Ikonic, P. Harrison, J. Zhang, D. J. Norris, A. G. Cullis, C. R. Pidgeon, P. Murzyn, B. Murdin, M. Bain, H. S. Gamble, M. Zhao, and W.-X Ni. IEEE Journal of Selected Topics in Quantum Electronics, 12(6), pp. 1570-1578, November-December 2006.

Temperature dependence of terahertz optical transitions from boron and phosphorus dopant impurities in silicon
S. A. Lynch, P. Townsend, G. Matmon, D. J. Paul, M. Bain, H. S. Gamble, J. Zhang, Z. Ikonic, R. W. Kelsall, and P. Harrison. Applied Physics Letters, 87:101114, September 2005.

Optical packet switching
E. Shekel, S. Ruschin, D. Majer, J. Levy, G. Matmon, L. Koenigsberg, J. Vecht, A. Geron, R. Harlavan, H. Shfaram, A. Arbel, T. McDermott and T. Brewer. Proceedings of the SPIE, Vol. 5625, Optical Transmission, Switching, and Subsystems II, February 2005, pp. 49-62.

Integrated optics beam deflectors
Eyal Shekel, Eli Rafaeli, Yedidya Ariel, Guy Matmon and Daniel Majer US Patents 6363185, 6370302, 6377733, 6459833, 6463196, 6504978, 6640030

Integrated optics beam deflectors and systems
Eyal Shekel, Daniel Majer, Shlomo Ruschin, Guy Matmon, Jacob Julian Vecht and Yedidia Ariel US Patents 6366709, 6366710, 6370284, 6374002, 6421476, 6487325, 6516102, 6519377, 6539133, 6542648, 6542649, 6556730, 6556731, 6584242, 6643435, 6684001

Integrated optics beam deflector assemblies utilizing side mounting blocks for precise alignment
Eyal Shekel, Eli Rafaeli, Yedidya Ariel, Guy Matmon and Daniel Majer US Patent 6366720

Method for producing an optical device and the optical device produced thereby
Eyal Shekel, Eli Rafaeli, Yedidya Ariel, Guy Matmon and Daniel Majer US Patent 6647178

Method for accurately mounting an optical element in an optical assembly
Eyal Shekel, Eli Rafaeli, Yedidya Ariel, Guy Matmon and Daniel Majer US Patent 6654524

Cylindrical lens alignment method
Guy Matmon, Eli Rafaeli and Eyal Shekel US Patent 6668118

Automatic optical inter-alignment of two linear arrangements
Eyal Shekel, Guy Matmon and Eli Rephaeli US Patent 6813023