Up-converted fir photonic source device integrating a dirac-like material with thz quantum cascade laser in on-chip geometry

Abstract

The present invention concerns an up-converted far-infrared photonic source device, comprising the following successive layers: - a ground material (110); - a hetero-structure of semiconductor material having a top surface (120); - a lithographic Bragg grating (125) on the top surface of the hetero-structure, the lithographic Bragg grating having a series of parallel slits with a pitch in the range of 15 to 30 μm; - an electrically powered n-doped conductive (130) with a gold top frame (131) injection contact on the top surface of the hetero-structure; - a dielectric layer (140) deposited on the lithographic Bragg grating; - a plasmonic grating (150,160) realized by a first electrically powered metallic layer (150) with a first series of slits matching the parallel slits of the Bragg grating and a series of second slits between each pair of slits of the first series of slits with a pitch in the range of 3-8 μm, and a second layer of a bi-dimensional conductive material (160) in contact with the first electrically powered metallic layer (150). The invention further concerns a manufacturing method for the up-converted far-infrared photonic source device.

Description

[0001]Up-converted FIR photonic source device integrating a Dirac-like material with THz quantum cascade laser in on-chip geometry ------ Applicant: Consiglio Nazionale delle Ricerche Inventors: Miriam Serena Vitiello, Alessandra Di Gaspare ------ The present invention concerns an up-converted FIR photonic source device integrating a Dirac-like material with THz quantum cascade laser in on-chip geometry. Background and prior art The generation of light across the mid-infrared (MIR) and terahertz (THz) frequency spectral regions has become an enabling technology, opening up a plethora of sensing applications across the physical, chemical and biological sciences, as well as enabling the study of fundamental light-matter interactions. The key disruptor in this domain is the quantum cascade laser (QCL) [1], which has grown from being a laboratory curiosity to an essential, practical and compact optoelectronic source for a broad range of application sectors. This expansion of applications has, however, highlighted a significant gap in technological capability between the MIR and THz regions, i.e. 25 µm – 60 µm (12 – 5 THz), which is termed the far-infrared (FIR) region. Unlike the neighboring MIR and THz regions, the FIR lacks a practical solid-state laser technology, owing to parasitic optical phonon absorption – the Restrahlenband – in the constituent III-V Jacobacci & Partners / ANP semiconductors used to fabricate QCLs. This is unfortunate, since there is a large number of applications that could be addressed by a compact FIR source. These range from sensing complex hydrocarbons in the petroleum-industry and astronomy, to understanding the intricacies of protein function in amino acids such as dipeptides and tripeptides [2] FIR sources are also an enabling technology for near-field microscopy in the solid state (phononics, plasmonics) [3] leading ultimately to their use in quantum optics, for example in the manipulation of Rydberg atoms for quantum computation architectures [4]. However, currently, there is no practical, spectrally narrowband, solid state-based technology to access the FIR. Available techniques are difficult to use or show poor performance. The most well-known approach is Fourier transform infra-red (FTIR) spectroscopy, which makes use of thermal sources. However, these sources are inherently incoherent, weak (~pW / nW over the FIR range) and spectrally broad. Other commercial systems make use of an ultrafast technique known as ‘time-domain spectroscopy’ (TDS), in which III-V photoconductive switches5 generate spectrally broad pulses of radiation. However, such systems are not compact, and emit most power in the range ~ 0.2 - 4THz, with bulky and expensive amplified lasers usually needed to extend the bandwidth into the FIR range using, for example, air plasma generation. The few narrowband sources, other than facility-based free electron lasers (FELs), are based on difference frequency generation in exotic gas lasers Jacobacci & Partners / ANP (e.g. 15NH3), but these are large and lack stability. Terahertz waves - electromagnetic waves with a frequency between the microwaves and mid-infrared - contain revolutionary potential for many applications that have been little exploited so far, due to the technological difficulties in creating efficient and practical devices. In particular, there are currently no compact and efficient sources capable of emitting waves at frequencies between 6 and 12 THz, due to the intrinsic physical limitations in the absorption mechanisms of the optical phonons constituting the main semiconductor sources existing today in this region of the electromagnetic spectrum (the so called “Reststrahlen” band) The potential applications of a source in this range (6-12 THz) are promising and varied. These sources could be used to study materials and chemical compounds, including aromatic hydrocarbons, fundamental for the energy sector and climate monitoring, or to investigate quantum phenomena in innovative materials such as topological insulators, for field applications, biomedical applications (diagnosis of tumors and skin pathologies, corresponding to specific absorption lines in this interval), cultural heritage, security in the postal and airport sectors. Ref. [7] discloses a grating-graphene metamaterial comprising a plasmonic grating realized by a conductive metal layer with a first series of slits with a period of 20 µm and a second layer of graphene, a, constituting a bi-dimensional conductive layer. The metamaterial is Jacobacci & Partners / ANP configured for a third harmonic signal of incident THz radiation and is suitable for realization of chip- integrated THz nonlinear conversion applications. The reported configuration works in the sub-THz range (700 GHz) and rely on a bulky, table top accelerator- based laser for optical (external pumping). Ref. [8] discloses a configuration for generating third harmonic generation at 9.63 THz by optically pumping single-Iayer graphene, which is free-space coupled to a circular split ring resonator array, with a 3.21 THz frequency quantum cascade laser. It relies on a metamaterial, pumped optically by an external laser. It therefore does not allow developing electrically pumped lasers at frequencies larger than the reported laser bandwidth (maximum frequency 3.4 THz). Ref. [9] discloses surface-emitting distributed feedback terahertz quantum-cascade lasers in metal-metal waveguides comprising a ground material; a photon- emitting active region hetero-structure of semiconductor material having a top surface; - a lithographic Bragg grating on the top surface of the hetero-structure, the lithographic Bragg grating having a series of parallel slits with a pitch in the range of 15 to 30 µm. The design allows operation at frequencies set by the bandwidth of the QCL and cannot exceed, by design, a frequency of 4 THz. Purpose and subject matter of the invention The purpose of the present invention is to provide an Jacobacci & Partners / ANP up-converted FIR photonic source device which solves the problems and overcomes the disadvantages of the prior art. The subject matter of the present invention is a device and a method according to the attached claims. Detailed description of invention embodiments List of figures The invention will now be described by way of illustration but not by way of limitation, with particular reference to the drawings of the attached figures, wherein: ^figure 1 shows (a) unit cell design of themetal / metal resonator for the realization of Bi2Se3 integrated QCL, used for the two -dimensional (2D) simulations, with the frequency domain module of COMSOL Multiphysics. The length of the unit cell along x equals the periodicity of the distributed feedback (DFB) array (25.5 µm). GaAs active region was modeled as a constant refractive index material in the THz range (n=3.6). DFB grating was realized by including one air hole with 0.7 ^m depth and 2.5 ^m width inside the doped layer, which constitutes the injection contact of the source. The refractive index of HfO2, as a gate dielectric with 100 nm thickness, was 4.24. An array of plasmonic gratings having periodicity of 1 / 5 of DFB periodicity was placed on top metal (conductive material), then coated with the Bi2Se3slits, thus realizing TI Jacobacci & Partners / ANP micro-ribbons embedded in the top metal, modeled as perfect electric conductor (PEC). Perfectly matched layer and PEC boundary conditions were selected in the top and bottom direction along z. The boundary condition along x was periodic. All the simulations were performed using a single periodic excitation port. (b) Real and imaginary part of the Bi2Se3 refractive index utilized in the 2D simulations [1,2];^ figure 2 shows a schematics (a) and scanningelectron microscope (SEM) images (b) of the invention device, featuring the DFB and the plasmonic grating on the top contact, and a field- effect architecture to provide the doping tuning on the BiSe-integrated film to actively control its optical conductivity, and thus the field coupling and confinement. The geometry of the plasmonic grating was chosen in agreement with the optimized design outcome of the simulation, with a plasmonic ribbon width Wpl = 2 µm.;^ figure 3 shows a (a) Light-current-voltage (L-I-V)curve measured on a prototype BiSe-integrated DFB plasmonic grating, measured while driving in pulsed mode with a pulse width of 1 µs (duty cycle 5%) at 15K, at gate voltage VG=+2 V (MNP, dark blue) and with the gate left floating (light blue). (b) FTIR emission spectrum acquired at a driving current corresponding to the peak optical power, on a DFB QCL with an integrated BiSe plasmonic grating, in rapid scan mode, under high vacuum, employing a Jacobacci & Partners / ANP cooled Si bolometer detector (by Infrared), and a spectral resolution of 0.075 cm-1, as a function of the gate voltage. from bottom to top: the gate voltage was spanned from VG-VD=-1 V to +3 V, in step of ΔVG=0.5V. c) Stacked emission spectra, acquired in step-scan mode in high vacuum, employing with a spectral resolution of 1 cm-1, after filtering out the fundamental harmonic emission with a Ta high-pass filter (cutoff 6 THz). The step scan signal was acquired employing a lock- in amplifier (by Stanford Instruments), synchronized with the AM signal at 317 Hz applied to demodulate the pulser driver of the QCL. In both (a,b), the traces are acquired at different gate voltages: VG= +3 V (black), +2 (red), 0 V (green), -1 V (blue) and -2 V(pink). (d) Conversion efficiencies (CE) extracted from the spectra of (b), at the Fermi energies corresponding to the employed gate voltages;^ figure 4 shows a (a) Third harmonic conversionefficiency (CE), as a function of the Fermi energy, calculated for the DFB / plasmonic resonator coated with 21 nm of BiSe topological insulator, employing the surface current density numerical model, by assuming an input port power of 300 mW, concentrated over the area of a single DFB slit, to mimic the laser intracavity power. (b) TH CE as a function of the intracavity power, calculated assuming EF=200 meV. (c) Comparison between the calculated CE (black line) and the CE retrieved experimentally, Jacobacci & Partners / ANP shown as a function of the corresponding intracavity power; ^Fig. 5 shows an alternative embodiment of theinvention device, with a spacer element of (a) 0,5 ^m, (b) 1 ^m, and (c) 5 ^m. It is specified here that elements of different embodiments can be combined together to provide further embodiments without limits while respecting the technical concept of the invention, as the skilled person understands without problems from what is here described. The present description also refers to the known art for its implementation, with regard to the detailed characteristics not described, such as for example elements of minor importance usually used in the known art in solutions of the same type. When introducing an element it always means that it can be "at least one" or "one or more". When a list of elements or characteristics is listed in this description it is meant that the invention "includes" or alternatively "is composed of" such elements. When features are listed within the same sentence or bulleted list, one or more of the individual features may be included in the invention without connection to the other features in the list. Two or more of the parts (elements, devices, systems) described below can be freely associated and considered as kits of parts according to the invention. Jacobacci & Partners / ANP Embodiments The invention consists in the creation of an integrated laser source based on a distributed feedback quantitative cascade laser with surface emission at frequency ^, integrated with a plasmonic grating, with pre-defined pitch, made with a topological insulator (e.g. BiSe) or with graphene two-dimensional (2D) materials. The ^ frequency induces a nonlinear mechanism of frequency up-conversion in the 2D material, leading to 3^ frequency emission with peak optical power levels > 6^W. This is the first up-converted FIR photonic source that integrate a Dirac-like material (e.g. BiSe or graphene) with THz QCLs (quantum cascade lasers) in on- chip geometry, taking advantage of the inherently TM (transverse-magnetic) polarized emission of QCLs. Making reference to Figs 1 and 2, an up-converted far-infrared photonic source device according to the invention comprises the following successive layers: ^a ground material 110, for example gold;^ a photon-emitting active region hetero-structure120 (QCL, quantum cascade laser) of semiconductor material having a top surface; ^a lithographic Bragg grating 125 (DFB) on the topsurface of the hetero-structure, the lithographic Bragg grating having a series of parallel slits 125 with a pitch in the range of 15 to 30 ^m (the width of each slit is not critical); ^an electrically powered conductive (n-dopedsemiconductor) injection contact 130 of the Jacobacci & Partners / ANP photonic source on the top surface of the hetero- structure; this covers the entire top surface of the active region except in the slit area, to allow the light out-coupling; ^a dielectric layer 140 (preferably an oxide layer)deposited on the lithographic Bragg grating; ^a plasmonic grating 150,160 realized by a firstelectrically powered conductive layer 150 with a first series of slits matching the parallel slits of the Bragg grating and a series of second slits between each pair of slits of the first series of slits with a pitch in the range of 3-8 ^m, and a second layer of a bi-dimensional conductive material 160 in contact with the first electrically powered conductive layer 150. The ratio between the periods of the second series of slits and the first series of slits can between 1 / 6 and 1 / 3, preferably between 1 / 5 and 1 / 4 for optimal efficiency of the device. The lithographic Bragg grating pitch can be parametrized according to the Bragg Law as a second order grating. The bidimensional material is known to be a material with only one of few atomic layers, preferably between 1 and 3 atomic layers. It can be a so-called topologic isolator, for example chosen the group comprising: graphene, Bi2Se3, chalcogenides topologic isolators, or in the group comprising: two-layered material of Bismuth Selenide on Indium Bismuth Selenide, three-layered material of Indium Bismuth on Selenide on Indium Bismuth Jacobacci & Partners / ANP Selenide, five-layered material of Indium Bismuth Selenide on Bismuth Selenide on Indium Bismuth Selenide on Bismuth Selenide on Indium Bismuth Selenide. In an embodiment according to Fig. 2, the dielectric layer 140 has a thickness in the range of 40-60 nm and the electrically powered metal (conductive material, preferably n-doped) 130 injection contact is deposited around the whole series of parallel slits. As an alternative solution, in the embodiment of Fig. 5, the dielectric layer 140 has a thickness in the range of 0.5-10 ^m and the electrically powered metal (conductive material) 130 injection contact is deposited on top of the whole series of parallel slits. This embodiment allows for an isolation of the parts of the device on the two sides of the dielectric layer, which optimize the laser source of the invention. In fact, such a dielectric layer (spacer) is introduced as layer 140 to substitute the oxide layer, with the purpose to enhance the electric field concentration in the 2D material active area, as an effect of the provided wave guiding architecture. This increases the efficiency of the high harmonic generation process. The manufacturing of the device comprises the following steps: ^providing a ground material 110 (e.g. Gold);^ providing a photon-emitting active regionheterostructure 120 having an end photon-emitting active semiconductor layer on a support semiconductor wafer; Jacobacci & Partners / ANP^ bonding the heterostructure 120 on the groundmaterial 110 on the side of the end photon-emitting active layer; ^removing the support semiconductor wafer;^ making a lithographic Bragg grating 125 on endphoton-emitting active semiconductor layer of the hetero-structure by etching parallel slits with a pitch in the range of 15 to 30 ^m; ^depositing an electrically powered n-dopedconductive injection contact 130 on the top surface of the hetero-structure; ^depositing a dielectric layer 140 on thelithographic Bragg grating 125; ^depositing a first conductive layer 150 with a firstseries of slits matching the parallel slits of the Bragg grating and a second series slits between each pair of slits of the first series of slits with a pitch in the range of 3-8 ^m; ^on top of the first conductive layer 150,transferring a second layer of a bi-dimensional conductive material 160 in contact with the first electrically powered conductive layer 150. As a benchmark device of the embodiment of Fig. 2, the Inventors engineered a one-dimensional distributed feedback (DFB) laser resonator, whose slit periodicity was tuned to match the center of the gain bandwidth (3.25-3.35 THz) of the selected QCL active region 120. To improve the field coupling, driving the FIR emission through harmonic generation in the nonlinear material, Jacobacci & Partners / ANP a grating-metamaterial field-enhancer has been integrated intracavity. It must be said in general that the invention comprises an electrically pumped source, where the light is generated by injecting current into an active region layer, followed by frequency up-conversion in the bidimensional material, via high-harmonic generation. In GaAs-based electrically pumped sources, engineered for far-infrared operation, fluorescence can be ruled out. Furthermore, nonlinear effects in other layers of the device can be excluded, since the related third-order nonlinearity is seven orders of magnitude lower, hence not suitable to provide the needed conversion efficiency The device 100 comprises a plasmonic grating patterned on the top of the DFB (distributed feedback) double-metal device (double conductive material), comprising a ground material 110 (usually Au ) and a hetero-structure 120 of semiconductor material having a top surface on which other layers are deposited. The result is then a double grating, top-contact resonator for the THz QCLs, featuring the 2nd order DFB 125, for the optimal control of the mode within the laser optical band, overlapped to a plasmonic grating 150,160, for field enhancement to drive the frequency up-conversion. The plasmonic / DFB design of this embodiment of the invention has been optimized by conducting a parametric study on the DFB resonator unit cell, the 2D structure shown in Fig.1a, whose size coincides with the Bragg lattice periodicity, LDFB=25.5 µm (in Fig. 2, the periodicity of slits 125 is the same as the periodicity Jacobacci & Partners / ANP of slits 151). With 160 a bi-dimensional conductive material is indicated, which is in contact with the first electrically powered conductive layer 150 and with the gate voltage. It is to be noted that the grating of the 2ndorder DFB 125 has a pitch in the range of 15 to 30 ^m and the powered conductive layer 150 has a first series of slits whose pitch matches the parallel slits of the 2ndorder DFB, while a series of second slits between each pair of slits of the first series of slits has a pitch in the range of 3-8 ^m. Between the hetero-structure 120 and the plasmonic grating 150,160, an oxide layer 140 is deposited on the lithographic Bragg grating of the heterostructure, preferably with thickness in the range of 40-60 nm. The integration of the Bi2Se3 material 160 into the resonator was realized in the benchmark design by defining the Bi2Se3as a transition boundary condition with assigned n,k (real and imaginary parts of the refractive index) optical constants and thickness tBiSe=21nm, calculated by following the method of [1,2] (See Fig. 1b), on each Air / GaAs interface of the plasmonic / DFB slits. To include the gate-tuning of the Fermi energy in the topological film 160, we defined a capacitor on the top device surface, including a gate voltage electrode 160. To this aim we inserted a 100 nm thick HfO2 layer (refractive index real part n=4.24, imaginary part k =0) 140 between the n-doped top layer of the QCL active region 120 and the top conductive grating 150. This will ensure the field-effect control Jacobacci & Partners / ANP of the free carriers in the Bi2Se3via gate voltage applied across the top conductive material (150) and the ground 110. The Inventors then performed a detailed modeling by varying the ribbon size Wpl (the width of the individual element of the plasmonic grating) in the plasmonic grating 150,160, to extract the lasing modes that simultaneously induce a strong nonlinear optical enhancement in the Bi2Se3160. After setting the geometry of the DFB plasmonic grating 150,160, the Inventors investigated the whole resonator operation. The fundamental mode and the field enhancement on the BiSe film was extracted, by running a 3D simulation of the entire DFB structure, optionally comprising the Cr side absorbers to suppress the Fabry-Perot cavity modes 155, these absorbers for the sake of simplicity are not included in the scheme of Fig. 2(a). To mitigate the increase of the total losses arising from the presence of a second grating on the top contact that could prevent the lasing itself, the Inventors integrated the plasmonic grating in the top contact region leaving the central part untouched. The device is realized by first patterning both the DFB and plasmonic gratings on the top n-doped layer, then transferring the BiSe active film. In the benchmark design, the top conductive contact 150 hosts the DFB grating 151,152, a linear array of 2.5 µm-wide, 800 nm-deep slits on the top conductive material / doped layer. In agreement with the simulated design, the DFB grating 151 infers the desired photonic Jacobacci & Partners / ANP momentum and frequency to the waveguide mode propagating along the longitudinal direction of the resonator bar, while the plasmonic ribbons 152 patterned on the lateral side of the laser bar proved the field enhancement for HHG (High Harmonic Generation). After having defined the top DFB grating, via optical lithography, followed by the removal of the doped GaAs from the slits, the resonator area was covered with a ~20nm-thick layer of HfO2140 via Atomic Layer Deposition (ALD); this approach enables field-effect gate-coupling of the film with the top emitting surface, and the electronic control of the doping level of the BiSe film 160. Then the Inventors realized, via electron beam lithography, the top plasmonic grating 150,160, by aligning (matching) the DFB / plasmonic grating pattern with the DFB slits etched underneath, as above mentioned. The transfer of the BiSe film was performed by using the PMMA-assisted wet method [3], employing a 30% NaOH solution to detach the topological insulator film from the Sapphire MBE substrate. The 21 nm thick BiSe film, once laid down on top of the QCLs, was patterned and removed from the area outside the DFB grating, via Ar- assisted reactive ion etching, in the production of multiple invention devices of the same type. To unveil the presence of a THG (Third Harmonic Generation) signal, the laser emission in step / scan mode in the Fourier Transform infrared (FITR) spectrometer was measured under vacuum. To isolate the high harmonic terms from the fundamental lasing modes a high-pass Tallium filter positioned in front of the detector was Jacobacci & Partners / ANP used that suppresses > 95% of the power below 6 THz, with a transmittance ≥50 % in the 6-7 THz range, and ≥ 70% at frequencies > 8 THz. The Inventors observed a decrease of the harmonic generation efficiency at increasing Fermi energies (Fig. 3), in overall agreement with the model, developed for Dirac-like systems [4,5]. The Inventors implemented a method to extract the THG efficiency as an output parameter directly from the simulation module, by setting up the equations for TH (Third Harmonic) generated field in Topological Insulator (TI) integrated on a plasmonic structure, and to link the conversion efficiency to the material properties, such as carrier mobility and doping, thus providing a further pathway toward the performance optimization. The TI film is anonlinear surface current generator, defined as ^^ = ^^^^^^^^^^ +^^3^^^^^^, where EFH and ETH are the electric fields induced at the fundamental and third harmonic, respectively, σg is the 2D film conductivity, calculated with the intraband Drude-like formula, and σ3 is the 3rd order non-linear conductivity. Under the assumption that the implemented model possesses a general validity in the context of Dirac systems, the TH conversion efficiency in the BiSe / QCL integrated devices was extracted by considering the optical parameters of the employed film, as measured in [1]. Namely, to include the TH conductivity on the surface density current generator, it was assumes the BiSe film as a double layer Dirac system with: EF=200 meV, vF=5^105m / s, µ=1500 cm2 / Vsand ^=121 fs. Jacobacci & Partners / ANP Figure 4 plots the TH conversion efficiency as a function of the intracavity power (Fig.4a) and of the Fermi level (Fig.4b), calculated under the same assumptions used for the graphene-integrated QCLs. Inventors’ model predicts a significant suppression (~50-70%) of the THG signal for moderate Fermi energy variation (~100 meV). This is in agreement with the experimental results, where the appearance of the TH peak sensitive to the gate voltage is consistently reproduced in most of the devices probed, for the gate voltages values that corresponded to the minimum conductivity in the 2D films. At the charge neutrality point (CNP), conversion efficacies as high as 10-3are expected. It is here remarked that the very low Fermi energies required to achieve such high CE, i.e. very close to the CNP (50 meV or less), are overall more difficult to reach in large area samples. An efficient route to increase the CE is then to include a gate-tuning electrode in the device design, to modulate the doping level of the nonlinear film during laser operation. This is done by inserting the gate dielectric layer 140 between the plasmonic contact and the laser doped layer top contact, so to realize the field-effect tuning of the carrier concentration on the TI film, through a bias port decoupled by the laser bias. Overall, very high CE are expected for intracavity powers (Fig.4a) of ~1W, a value that could be within the realm of the employed high-power active region. Fig. 5 shows a further enhancement of the invention device, wherein an electrical field map is shown, wherein Jacobacci & Partners / ANP a spacer is introduced as layer 140 to substitute the oxide layer, with the purpose to enhance the electric field concentration in the 2D material active area, as an effect of the provided wave guiding architecture (see above). Some advantages of the invention The potential applications of the invention device as a source in the range (6-12 THz) are many. These sources can be used to study materials and chemical compounds, including aromatic hydrocarbons, fundamental for the energy sector and climate monitoring, or to investigate quantum phenomena in innovative materials such as topological insulators, for field applications, biomedical applications (diagnosis of tumors and skin pathologies, corresponding to specific absorption lines in this interval), cultural heritage, security in the postal and airport sectors. The developed technology will also open up new application areas and is therefore strategically relevant for the market. These include: 1) Quantum control of condensed matter, for example of the Si:P atom-in-semiconductor system that has been proposed for quantum computing applications. In this case, while the qubit is encoded in nuclear splitting in the microwave range, the 1s-2p transition of the trapped P atom is in the far-IR region, around 8THz. This transition has been used to consistently control the state of the qubits, but is currently only accessible via facilities as FEL requires as a path for switching 2-qubit interactions, Jacobacci & Partners / ANP thus making this application impossible; 2) Studies on complex liquids such as water in the FIR: there are strong absorptions that have not been widely studied due to the lack of appropriate sources. Coherent FIR studies will provide new information on low-frequency intermolecular motions that have not been available from conventional thermal sources. This could provide vital information, for example, on the complex interaction of water molecules with atmospheric gases and their role in the mesostructures (proteins and charge groups) of biological organisms, as well as enabling the rapid detection of complex amino acids; 3) diagnostics in the troposphere and ionosphere and detection of resonant substances. References [1] J. Faist, Quantum Cascade Lasers (Oxford Uni. Press, NY, 2018). [2] K. Feng et al, Opt. Express 23, A1418 (2015). [3] D.N. Basov et al, Rev. Mod. Phys. 86, 959 (2014). [4] Y. He et al, Nature 571, 371 (2019). [5] N.M. Burford et al, Opt. Eng. 56, 010901 (2017). [6] H. Odashima, et al, Opt. Lett. 24, 406 (1999). [7] DEINERT JAN-CHRISTOPH ET AL: "Grating-Graphene Metamaterial as a Platform for Terahertz Nonlinear Photonics", ACS NANO, vol. 15, no. 1, 11 December 2020 (2020-12-11), pages 1145-1154. [8] DI GASPARE ALESSANDRA ET AL: "Compact terahertz harmonic generation in the Reststrahlenband using a Jacobacci & Partners / ANP graphene-embedded metallic split ring resonator array", NATURE COMMUNICATIONS, vol. 15, no. 1, 14 March 2024. [9] KUMAR SUSHIL ET AL: "Surface-emitting distributed feedback terahertz quantum-cascade lasers in meta)-meta) waveguides", OPTICS EXPRESS, vol. 15, no. 1, 1 January 2007 (2007-01-01), page 113. In the foregoing, the preferred embodiments have been described and variations of the present invention have been suggested, but it is to be understood that those skilled in the art will be able to make modifications and changes without thereby departing from the relevant scope of protection, as defined by the claims attached. Jacobacci & Partners / ANP

Claims

CLAIMS 1. Up-converted far-infrared photonic source device, comprising the following successive layers: ^a ground material (110);^ a photon-emitting active region hetero-structure(120) of semiconductor material having a top surface; ^a lithographic Bragg grating (125) on the topsurface of the hetero-structure, the lithographic Bragg grating having a series of parallel slits with a pitch in the range of 15 to 30 ^m; ^an electrically powered n-doped conductive (130)injection Gold frame contact (131) on the top surface of the hetero-structure on the outer region of said series of parallel slits; ^a dielectric layer (140) deposited on thelithographic Bragg grating; ^a plasmonic grating (150,160) realized by a firstelectrically powered conductive layer (150) with a first series of slits matching the parallel slits of the Bragg grating and a series of second slits between each pair of slits of the first series of slits with a pitch in the range of 3-8 ^m, and a second layer of a bi-dimensional conductive material (160) in contact with the first electrically powered conductive layer (150).

2. Up-converted far-infrared photonic source device Jacobacci & Partners / ANPaccording to claim 1, wherein the dielectric layer (140) has a thickness in the range of 40-60 nm.

3. Up-converted far-infrared photonic source device according to claim 1, wherein the dielectric layer (140) has a thickness in the range of 0.5-10 ^m.

4. Up-converted far-infrared photonic source device according to any claim 1 to 3, wherein the ratio between a period of second series of slits and a period of the first series of slits is between 1 / 6 and 1 / 3.

5. Up-converted far-infrared photonic source device according to claim 4, wherein the ratio is between 1 / 5 and 1 / 4.

6. Up-converted far-infrared photonic source device according to any claim 1 to 5, wherein the bidimensional material has a number of atomic layers between 1 and 3.

7. Up-converted far-infrared photonic source device according to any claim 1 to 6, wherein the bidimensional material is a topologic isolator.

8. Up-converted far-infrared photonic source device according to claim 7, wherein the topological isolator is chosen in the group comprising: graphene, Bi2Se3, chalcogenides topologic isolators.

9. Up-converted far-infrared photonic source device Jacobacci & Partners / ANPaccording to claim 7, wherein the topological isolator is chosen in the group comprising: two-layered material of Bismuth Selenide on Indium Bismuth Selenide, three- layered material of Indium Bismuth on Selenide on Indium Bismuth Selenide, five-layered material of Indium Bismuth Selenide on Bismuth Selenide on Indium Bismuth Selenide on Bismuth Selenide on Indium Bismuth Selenide.

10. Up-converted far-infrared photonic source device according to any claim 1 to 9, wherein the ground material is gallium arsenide.

11. Method for the manufacturing an up-converted far- infrared photonic source device, wherein the following steps are performed: A. providing a ground material (110);B. providing an photon-emitting active regionheterostructure (120) having an end photon- emitting active semiconductor layer on a support semiconductor wafer; C. bonding the heterostructure (120) on the groundmaterial (110) on the side of the end photon- emitting active layer; D. removing the support semiconductor wafer;E. making a lithographic Bragg grating (125) on endphoton-emitting active semiconductor layer of the hetero-structure by etching a series of parallel slits, down to an n-doped conductive injection contact (130), with a pitch in the range of 15 to 30 ^m; Jacobacci & Partners / ANPF. contacting the n-doped conductive injectioncontact layer (130) with a gold frame (131) on the top surface of the hetero-structure on the outer region of said series of parallel slits; G. depositing a dielectric layer (140) on thelithographic Bragg grating (125); H. depositing a first conductive layer (150) with afirst series of slits matching the parallel slits of the Bragg grating and a second series slits between each pair of slits of the first series of slits with a pitch in the range of 3-8 ^m; I. on top of the first conductive layer (150),transferring a second layer of a bi-dimensional conductive material (160) in contact with the first electrically powered conductive layer (150).

12. Method according to claim 11, wherein the dielectric layer (140) has a thickness in the range of 40-60 nm and the electrically powered conductive (130) injection contact is deposited around the whole series of parallel slits.

13. Method according to claim 11, wherein the dielectric layer (140) has a thickness in the range of 0,5-10 ^m and the electrically powered n-doped conductive (130) injection contact is deposited on top of the whole series of parallel slits.

14. Method according to any claim 11 to 13, wherein Jacobacci & Partners / ANPthe ratio between a period of the second series of slits and a period of the first series of slits is between 1 / 3 and 1 / 6.

15. Method according to claim 14, wherein the ratio is between 1 / 4 and 1 / 5.

16. Method according to any claim 11 to 15, wherein the bidimensional material has a number of atomic layers between 1 and 3.

17. Method according to any claim 11 to 16, wherein the bidimensional material is a topologic isolator.

18. Method according to claim 17, wherein the topological isolator is chosen in the group comprising: graphene, Bi2Se3, chalcogenides topologic isolators.

19. Method according to claim 17, wherein the topological isolator is chosen in the group comprising: two-layered material of Bismuth Selenide on Indium Bismuth Selenide, three-layered material of Indium Bismuth on Selenide on Indium Bismuth Selenide, five- layered material of Indium Bismuth Selenide on Bismuth Selenide on Indium Bismuth Selenide on Bismuth Selenide on Indium Bismuth Selenide.

20. Method according to any claim 11 to 19, wherein the ground material is gallium arsenide. Jacobacci & Partners / ANP

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