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Publication List Articles Published or under revision in Peer-Reviewed Journals < Back Poster: “Hydrogenation-Driven Bandgap Engineering in InN Nanowires for Quantum Technologies and Optoelectronic Devices” Conference: Nanowire Week 2025 Date, where: 25 – 29/08/2025, St John’s College, University of Cambridge, Cambridge, UK Authors: Muhammad Tahir, Francesca Santangeli, Pietro Todesco, Ernesto Placidi, Marco Sbroscia, Zetian Mi, Songrui Zhao, Antonio Polimeni, and Marta De Luca.

Organized Conferences Marta co-organizes the IEEE Nanotechnology Materials and Devices Conference in October 2023, Paestum, Italy . Symposium ‘Fundamentals and applications of nanotubes, nanowires, quantum dots and other low dimensional materials’ Marta co-organizes the CLEO/Europe Focus Meeting (ECOC, European Conference on Optical Communication) in September 2022, Basel, Switzerland. Symposium ‘Novel Photonic Materials & Effects’ Invited Talks Marta gives a talk for the International Symposium on Semiconductor Optoelectronics and Nanotechnology (ISSON) in the Department of Electronic Materials Engineering of the Australian National University on the 9.11.2024. Marta gives an invited talk for the Quantum Science & Technology Seminars in the Physics Department of Federico II University in Naples (Italy) on the 27.10.2023. Marta gives an invited talk at the IEEE Nanotechnology Materials and Devices Conference (NMDC) in Paestum (Italy) on the 24.10.2023. https://ieeenmdc.org/past-conferences/nmdc-2023/ Marta gives an invited talk at the Phonons Conference 2023 in Paris (France) on the 05.07.2023 https://phonons2023.sciencesconf.org/ Marta gives an invited talk at the International Conference on Solid State Devices and Materials (SSDM) in Chiba (Japan) on 27.09.2022 https://ssdm.jp/2022/ Marta gives an invited talk at the Rank Prize symposium on Nanowire Photonics in Grasmere in Lake District (UK) on 08.11.2022 https://www.rankprize.org/symposia/nanowire-photonics-2/

Publication List Articles Published or under revision in Peer-Reviewed Journals < Back 1. Surfactant Free Platinum Nanoclusters as Fluorescent Probe for the Selective Detection of Fe(III) Ions Anu George, Harikrishnan G., Sukhendu Mandal* (Sens.Actuators B 243 (2017)332- 337). 2. Negative photoresponse of ZnO-PEDOT:PSS nanocomposites and photogating effects Harikrishnan G.*, Sesha Vempati, K Bandopadhyay, K. Prajapati, Vijith Kalathingal and J. Mitra* (Nanoscale Advances,1 (2019)2435). 3. Epsilon-near-zero response in Indium Tin Oxide thin fims: Octave span tuning and IR plasmonics Ben Johns, Navas M P, Harikrishnan G., Akhileshwar Mishra, Ravi Pant, J. Mitra* (Journal of Applied Physics 127(4):043102(2020)). 4. Enhancement in electrical conductivity of a porous indium based metal-organic framework upon 12 uptake: combined experimental and theoretical investigations Mani Prabhu, Mandal Nilangshu, Roopesh Mekkat, Harikrishnan G., Datta Ayan, Mandal Sukhendu* (Journal of Materials Chemistry C 8(14):4836-4842(2020)). 5. Controlling the macroscopic electrical properties of reduced graphene oxide by nanoscale writing of electronic channels Arijit Kayal, Harikrishnan G.,K. Bandopaghyay, Amit Kumar, S. Ravi P. Silva, J.Mitra* (Nanotechnology, 2021.32(17):p.175202). 6. Mobility enhancement in CVD-grown monolayer MoS2 via patterned substrate induced non-uniform straining Arijit Kayal, Sraboni Dey, Harikrishnan G., Nadarajan Renjith, Chattopadhyay Shashwata, J.Mitra* (Nano Lett. 2023, 23, 14, 6629-6636). 7. Anomalous Photoresponse in a Reduced Metal- Semiconductor Hybrid of Nickel and Titanium Oxide Harikrishnan G., K. Bandopadhyay, K. Kolodziejak, Vinayak B Kamble, Dorota A. Pawlak, J.Mitra * (arXiv:2309.17427 [physics.app-ph]). 8. Negative resistance and anomalous transport properties of a porous anisotropic (Ni- TiO2) hybrid system Harikrishnan G., Shashwata Chattopadhyay, K. Bandopadhyay, K. Kolodziejak, Dorota A. Pawlak, J.Mitra * (arXiv:2310.02976 [cond-mat.mtrl-sci]). Poster : “Comprehensive Raman toolkit to probe crystal quality, geometry, and vibrational properties of InN nanowires” Conference: Nanowire Week 2025 Date, where: 25 – 29/08/2025, St John’s College, University of Cambridge, Cambridge, UK Authors: Harikrishnan Gopalakrishnan, Francesca Santangeli, Pietro Todesco, Muhammad Tahir, Ernesto Placidi, Francesco Mura, Zetian Mi, Songrui Zhao, and Marta De Luca.

PRIN Project Nanowires (NWs) are quasi-1D crystals with nanoscale diameters and several microns in length. This project aims at growing and thoroughly investigating quantum dots (QDs) and superlattices (SLs) in two different III-V NW heterostructures: GaAsP/GaP NWs, for photonic and optoelectronic applications in the visible-near infrared range, and InAsP/InP NWs, for telecom-wavelengths applications. The well-known vapor-liquid-solid growth approach will be employed to realize bottom-up NWs incorporating QDs of controllable size, position and chemical composition. In particular, we will use the chemical beam epitaxy technique, which combines the advantages of ultra-high-vacuum epitaxial growth with the ease of use and flexibility given by metalorganic precursor gas sources. The controlled NW morphology and diameter will be exploited for the optimization of the waveguiding properties of NWs for the nested QDs. Scanning electron microscopy (SEM) for morphology characterization and energy dispersive x-ray spectroscopy (EDX) for compositional analysis are performed in-house with a field emission gun (FEG) electron microscope operating up to 30 kV. Electron Beam Lithography (EBL) for substrate patterning is performed instead with a dedicated FEG SEM equipped with an interferometric stage. The CNR unit in Pisa has a remarkable expertise in the growth and structural characterization of III-V semiconductor nanowires, axial and radial nanowire heterostructures, and selective area nanostructures. The Chemical Beam Epitaxy (CBE) system and the cleanroom facility of the National Enterprise for nanoScience and nanoTechnology (NEST) Laboratory of Scuola Normale Superiore, where the Nanoscience institute of CNR is headquartered are fully available for the project.The CBE is equipped with a Riber Compact-21 growth chamber with an integrated Reflection of High Energy Electron Diffraction (RHEED) system for in-situ monitoring and an optical pyrometer for the substrate temperature measurement. Available group-V materials are arsenic (TBAs), phosphorous (TBP), and antimony (TDMASb and TMSb); for group III there are indium (TMIn), gallium (TEGa), and aluminium (TMAl) precursors. Transmission electron microscopy (TEM) to investigate the nanowires structural quality (crystal phase, interface sharpness, strain distribution) is also performed by the CNR unit, in collaboration with the Center for Instrument Sharing (CISUP) of the University of Pisa. R. Sorodoc, P. De Vincenzi, ACS Appl. Mater. Interfaces 16, 47 (2024) The growth and the structural characterization of the NWs performed at the CNR unit is cross-correlated to advanced optical spectroscopy experiments (inelastic light scattering and photoluminescence) carried out at Sapienza University. The optical measurements are performed also with a photon-correlation setup to probe the properties of the grown QDs. The close synergy of the two units allows a continuous flow of samples and information. In this way, a full picture of the structural, electronic, and optical properties of the QDs and SLs in NWs is achieved and controllably tuned. Single QDs in NWs with high brightness and low multi-photon emission probability are being realized within this project, as well SLs with a tunable period, in order to determine the new type of band alignment arising in the SL and show the potential of these SLs for NW-based optoelectronic applications such as photodetectors. Furthermore, NWs with GaAsP (with varying concentrations of As and P) in the wurtzite phase were created to study the new optical and electronic properties of the material in this new crystalline phase. The results of this study are then used as a starting point to better understand the effects of quantum confinement in the previously mentioned samples. Team members: Dr. Valentina Zannier, CNR researcher Prof. Marta De Luca, Sapienza University professor Prof. Lucia Sorba, CNR research director Robert Andrei Sorodoc, CNR fellow Paolo De Vincenzi, PhD student of Sapienza University Giada Bucci, PhD student of Scuola Normale Superiore Publications: Tunable GaAsxP1-x quantum dot emission in wurtzite GaP Nanowires . R. Andrei Sorodoc+, P. De Vincenzi+, A. Sagar Sharma, G. Bucci, M. Roggi, E. Mugnaioli, L. Sorba, M. De Luca and V. Zannier (+ equal contribution). ACS Appl. Mater. Interfaces 16, 47 (2024) Zincblende InAsxP1–x/InP Quantum Dot Nanowires for Telecom Wavelength Emission. G. Bucci*, V. Zannier, F. Rossi, A. Musiał, J. Boniecki, G. Sęk, L. Sorba. ACS Appl. Mater. Interfaces 16, 20 (2024) InAs–InP Superlattice Nanowires with Tunable Phonon Frequencies, V. Zannier, J. Trautvetter, A. K. Sivan, F. Rossi, D. de Matteis, B. Abad, R. Rurali, L. Sorba, I. Zardo. Advanced Physics Research 3, 6 (2024) Revealing Inclined Twin Related Defects in III–V Nanowires Grown in Popular Alternative Crystallographic Directions, H. A. Fonseka, N. Denis, J. A. Gott, X. Yuan, R. Beanland, H. H. Tan , C. Jagadish, A. M. Sanchez, M. De Luca*. J. Phys. Chem. C 2024, 128, 50 (2024)

Open Positions WHAT WE REQUIRE: Passion for designing and developing new experiments from scratch Thirst for knowledge Excellent communication skills and marked team spirit WHAT WE OFFER: A passionate, young and multidisciplinary group Special attention to diversity, both in gender and in nationality Candidates from all over the world and with all genders are welcomed Post-doc We have one open post-doc position on the ERC grant. Here are the details . PhD Student We have 1 open PhD position. The PhD in Italy lasts 3 years . PhD students do not have teaching duties but only research duties. However, in the first 1.5 years they have to attend courses and give exams. Admission to the PhD schools is very competitive and takes place only once a year, typically in June, for starting the PhD in November. Admission is decided by a committee, not by the Nanospectrosocpy group. However, before applying, you will have to send an email to marta.deluca@uniroma1.it with your CV and short motivation, and you may be asked to do an oral interview with the Nanospectrosocpy group before you submit your application to the PhD schools. There are two main PhD schools. Here you can find information on how to apply and which courses you can attend: PhD school in Physics (https://phd.uniroma1.it/web/PHYSICS_nD3503_EN.aspx ) PhD school in Materials Science (https://phd.uniroma1.it/web/MATHEMATICAL-MODELS-FOR-ENGINEERING,-ELECTROMAGNETICS-AND-NANOSCIENCES_nD3523_EN.aspx ) Master Student We have 2 open positions per year, and about 4-5 different projects. Contact marta.deluca@uniroma1.it to know more about the projects and do a lab tour. We welcome students from different Departments, ranging from Physics to Nanoscience and Chemistry.

ERC Project The group hosts the ERC Starting grant of Marta De Luca. NANOWHYR: Dots-in-NANOWires by near-field illumination: novel single-photon sources for HYbRid quantum photonic circuits The project aims at creating movable quantum light emitters for photonic circuits. In silicon-based quantum photonic circuits, a significant challenge is the efficient integration of a III-V-based single photon source. We are utilizing semiconductor nanowires because they can be grown directly on silicon or transferred to it after growth. When a nanowire incorporates a single photon emitter, such as a quantum dot, it becomes a movable light source. We are exploring the fabrication of quantum light emitters via a combination of hydrogenation and near-field illumination. This method enables the creation of an arbitrary number of quantum light emitters, which can be controlled in energy and position, allowing for integration in cavities.

< Back Harikrishnan Gopalakrishnan Post-Doc Researcher Curriculum Vitae Publications since 2025 Postdoctoral Researcher in Nano-spectroscopy group, Department of Physics, Sapienza University of Rome, Italy. Supervisor: Prof. Marta De Luca. 2023-2024 Postdoctoral Researcher in the Scanning Probe Microscopy and Plasmonics Group, School of Physics, Indian Institute of Science Education and Research, Thiruvananthapuram, Kerala, India. Project: Harnessing direct and indirect excitons in TMDCs for photo-stimulated device applications (STARS-MoE, Govt of India) PI: Prof. Joy Mitra. Project: Functionalizing the next-generation 2D semiconductors for optoelectronic and catalytic applications via ion irradiation (SPARC-UKIERI) PI’s: Prof. Ravi Silva, Director, ATI. Prof. Satheesh Krishnamurthy, Director, Ion Beam Center, University of Surrey, UK & Prof. Joy Mitra, IISER TVM 2017-2023 Ph.D. in Physics (INSPIRE Fellowship, Department of Science and Technology, Govt of India) School of Physics, Indian Institute of Science Education and Research, Thiruvananthapuram, Kerala, India. Supervisor: Prof. Joy Mitra. Thesis Title : Optoelectronic and Transport Properties of Nanostructured Hybrids of ZnO PEDOT:PSS and Ni-TiO2. Indo-Poland Joint Project (2020-2023) A novel heterostructure architecture for photodetection and photo-enhanced electron emission applications (Indo-Poland Project); Prof. Dorota A. Pawlak, Institute of Electronic Materials Technology, Department of Functional Materials, University of Warsaw, Poland. Exchange Visit Student (2018) Nanoscale writing of bespoke Graphene devices for electronic and plasmonic scalable technologies (UGC-UKIERI); Prof. Ravi P Silva, Advanced Technology Institute (ATI), University of Surrey, UK. 2016-2017 Project Assistant School of Physics, Indian Institute of Science Education and Research, Thiruvananthapuram, Kerala, India. Supervisor: Prof. Joy Mitra Project: Nanoscale Schottky Junction for sub-ppm hydrogen detection (DST-SERB Grant) 2011-2016 BS MS Integrated Dual Degree; Physics (Major) and Chemistry (Minor) Indian Institute of Science Education and Research, Thiruvananthapuram, Kerala, India. Back to Top Sapienza University of Rome, Physics Department harikrishnan.gopalakrishnan@uniroma1.it Office: n° 349, third floor, Marconi building, Physics Department

< Back Muhammad Tahir PhD Student Curriculum Vitae Publications Since 2023 PhD Student, Nanospectroscopy Group, Department of PhysicsSapienza University of Rome, Italy. Currently focusing on tuning the optoelectronic and thermoelectric properties of indium nitride (InN) nanowires. 2018-2020 Master of Science (MSc) in PhysicsCOMSATS University Islamabad, Pakistan 2013-2017 Bachelor of Science (BSc) in PhysicsBahauddin Zakariya University, Multan, Pakistan Back to Top Sapienza University of Rome, Physics Department muhammad.tahir@uniroma1.it Office: n° 349, third floor, Marconi building, Physics Department

Projects Single photon emitters in GaAsN nanowire tubes Bandgap engineering and strain engineering by hydrogenation in dilute nitrides nanowires Defect engineering and bandgap control in InN nanowires Tunable quantum dots in GaAsP and InAsP nanowires Micro-ring resonator lasers by self-assembly in InP Size-controlled and site-controlled quantum rings in quantum wells Unveiling new crystalline defects in InP nanowires Spectroscopic investigations on Hybrid 2D Perovskites

Collaborations - Prof. F. Ishikawa, Hokkaido University (Japan) - Prof. S. Zhao and Prof. Z. Mi, Mc Gill University (Canada) - Prof. H. Tan and Prof. C. Jagadish, Australian National University (Australia) - Prof. A. Fontcuberta i Morral, EPFL (Switzerland) - Prof. L. Sorba, Dr. V. Zannier, CNR nano and Scuola Normale Superiore (Italy) - Dr. S. Rubini, CNR Tasc (Italy) - Prof. A. Sanchez, Warwick University (UK) - Dr. R. Rurali, ICMAB (Spain) - Prof. I. Zardo, University of Basel (Switzerland) - Prof. A. Polimeni and Prof. M. Felici, Sapienza University (Italy) Fundings GROUNDS : Growth and optical studies of tunable quantum dots and superlattices in semiconductor nanowires HELIOS : Bright telecom-band single photon sources in bottom-up nanowire waveguides Development of single photon quantum states based on quantum dots operating at different wavelengths NANOWHYR : Dots-in-NANOWires by near-field illumination: novel single-photon sources for HYbRid quantum photonic circuits

< Back Pietro Todesco Master Student Curriculum Vitae Publications 2022-2024 Master of Science (MSc) in Condensed Matter Physics at Sapienza University, Rome. Completed his master’s thesis in the Nanospectroscopy Group at the Physics Department of the Sapienza University, focusing on bandgap engineering of InN nanowires. 2019-2022 Bachelor of Science (BSc) in Physics at Sapienza University, Rome Back to Top Sapienza University of Rome, Physics Department Office:

Team Members Marta De Luca Principal Investigator Office: n° 350, third floor, Marconi building, Physics Department Read More Francesca Santangeli PhD Student Office: n° 349, third floor, Marconi building, Physics Department Read More Muhammad Tahir PhD Student Office: n° 349, third floor, Marconi building, Physics Department Read More Akant Sagar Sharma Post-Doc Researcher Office: n° 349, third floor, Marconi building, Physics Department Read More Paolo De Vincenzi PhD Student Office: n° 312, third floor, Marconi building, Physics Department Read More Isabella Santanchè Master Student Office: n° 312, third floor, Marconi building, Physics Department Read More Harikrishnan Gopalakrishnan Post-Doc Researcher Office: n° 349, third floor, Marconi building, Physics Department Read More Riccardo Pallucchi PhD Student Office: n° 349, third floor, Marconi building, Physics Department Read More Alumni Research Assistant Xiangyu Lin Read More Master Student Pietro Todesco Read More Master Student Mario Roggi Read More