Quantum light emitters based on semiconductor quantum dots (QDs) have shown great potential for advanced quantum optics and nanophotonic applications. Among these, tunable GaAsₓP₁–ₓ QDs embedded in nanowires (NWs), capable of emission in the visible to near-infrared range, represent a particularly attractive yet unexplored platform. We report the synthesis of high-purity wurtzite GaP NWs incorporating single GaAsₓP₁–ₓ QDs with varying As content. Low-temperature microphotoluminescence (μ-PL) spectroscopy confirms both the well-defined quantum confinement and the emission wavelength tunability as a function of the As composition: the optical emission is dominated by a narrow spectral peak, whose position shifts from ~650 nm (As = 70%) to ~720 nm (As = 90%), demonstrating effective emission energy engineering through compositional control (see Fig. 1, leftside panel). Moreover, single-NW μ-PL mapping reveals a localized and efficient carrier recombination mechanism, confirming that the observed emission originates from the QD. Power- and temperature-dependent μ-PL measurements are carried out to investigate the excitonic properties of the QD and to understand the origin and nature of the involved energy levels [1]. To demonstrate the quantum nature of the emitters, second-order time-correlation (g²(τ)) measurements were performed under both continuous-wave and pulsed excitation. Under pulsed excitation, the results yield g²(0) ~ 0.1, confirming the single-photon emission character of the narrow spectral lines (see Fig. 1, right side panel)[2]. This observation provides evidence that the emission arises from individual QDs and establishes the potential of these NW-based GaAsₓP₁–ₓ QDs as high-quality, energy-tunable quantum light sources. Lastly, NWs with GaAsₓP₁–ₓ segments (with As content ranging from 20% to 90%) in the wurtzite phase were fabricated. These structures are valuable for understanding the QD confinement and offer a unique opportunity to investigate the fundamental properties of a new class of wurtzite-based crystals.
Quantum light emission from tunable GaAsxP1-x quantum dots in wurtzite GaP nanowires / De Vincenzi, Paolo; Sharma, Akant Sagar; Andrei Sorodoc, Robert; Bucci, Giada; Roggi, Mario; Santanchè, Isabella; Mugnaioli, Enrico; Sorba, Lucia; Zannier, Valentina; De Luca, Marta. - (2025). (Intervento presentato al convegno Nanowire Week 2025 tenutosi a St John’s College, University of Cambridge Cambridge, UK).
Quantum light emission from tunable GaAsxP1-x quantum dots in wurtzite GaP nanowires
Paolo De Vincenzi;Akant Sagar Sharma;Lucia Sorba;Marta De Luca
2025
Abstract
Quantum light emitters based on semiconductor quantum dots (QDs) have shown great potential for advanced quantum optics and nanophotonic applications. Among these, tunable GaAsₓP₁–ₓ QDs embedded in nanowires (NWs), capable of emission in the visible to near-infrared range, represent a particularly attractive yet unexplored platform. We report the synthesis of high-purity wurtzite GaP NWs incorporating single GaAsₓP₁–ₓ QDs with varying As content. Low-temperature microphotoluminescence (μ-PL) spectroscopy confirms both the well-defined quantum confinement and the emission wavelength tunability as a function of the As composition: the optical emission is dominated by a narrow spectral peak, whose position shifts from ~650 nm (As = 70%) to ~720 nm (As = 90%), demonstrating effective emission energy engineering through compositional control (see Fig. 1, leftside panel). Moreover, single-NW μ-PL mapping reveals a localized and efficient carrier recombination mechanism, confirming that the observed emission originates from the QD. Power- and temperature-dependent μ-PL measurements are carried out to investigate the excitonic properties of the QD and to understand the origin and nature of the involved energy levels [1]. To demonstrate the quantum nature of the emitters, second-order time-correlation (g²(τ)) measurements were performed under both continuous-wave and pulsed excitation. Under pulsed excitation, the results yield g²(0) ~ 0.1, confirming the single-photon emission character of the narrow spectral lines (see Fig. 1, right side panel)[2]. This observation provides evidence that the emission arises from individual QDs and establishes the potential of these NW-based GaAsₓP₁–ₓ QDs as high-quality, energy-tunable quantum light sources. Lastly, NWs with GaAsₓP₁–ₓ segments (with As content ranging from 20% to 90%) in the wurtzite phase were fabricated. These structures are valuable for understanding the QD confinement and offer a unique opportunity to investigate the fundamental properties of a new class of wurtzite-based crystals.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
