Photocathodes and Microchannel Plates

We report on the high performance solar-blind AlGaN-based p-i-n photodetectors that are grown by metal-organic chemical vapor deposition on c-plane sapphire substrates. The dark current of the 200μm diameter devices was measured to be on the order of 5fA for bias voltages up to 10V. The breakdown voltages were higher…

• TURGUT TUT

The transport properties of high mobility AlGaN/AlN/GaN and high sheet electron density AlInN/AlN/GaN two-dimensional electron gas (2DEG) heterostructures were studied. The samples were grown by metal-organic chemical vapor deposition on c-plane sapphire substrates. The room temperature electron mobility was measured…

• MEHMET KASAP

The transport properties of high mobility AlGaN/AlN/GaN and high sheet electron density AlInN/AlN/GaN two-dimensional electron gas (2DEG) heterostructures were studied. The samples were grown by metal-organic chemical vapor deposition on c-plane sapphire substrates. The room temperature electron mobility was measured…

• ALİ TEKE

The prospect of pileup induced backgrounds at the High Luminosity LHC (HL-LHC) has stimulated intense interest in developing technologies for charged particle detection with accurate timing at high rates. The required accuracy follows directly from the nominal interaction distribution within a bunch crossing ( σ z ∼ 5…

We report on the high efficiency tunnel-injected ultraviolet light emitting diodes (UV LEDs) emitting at 287 nm. Deep UV LED performance has been limited by the severe internal light absorption in the p-type contact layers and low electrical injection efficiency due to poor p-type conduction. In this work, a polarizat…

• FATİH AKYOL

In the present study, we reported the results of the investigation of electrical and optical measurements in AlxGa1−xN/GaN heterostructures (x=0.20) that were grown by way of metal-organic chemical vapor deposition on sapphire and SiC substrates with the same buffer structures and similar conditions. We investigated t…

• SEFER BORA LİŞESİVDİN

In the present study, we reported the results of the investigation of electrical and optical measurements in AlxGa1−xN/GaN heterostructures (x=0.20) that were grown by way of metal-organic chemical vapor deposition on sapphire and SiC substrates with the same buffer structures and similar conditions. We investigated t…

• MEHMET KASAP

InGaN/GaN tunnel junction contacts were grown using plasma assisted molecular beam epitaxy (MBE) on top of a metal-organic chemical vapor deposition (MOCVD)-grown InGaN/GaN blue (450 nm) light emitting diode. A voltage drop of 5.3 V at 100 mA, forward resistance of 2 × 10−2 Ω cm2, and a higher light output power compa…

• FATİH AKYOL

We report on tunnel-injected deep ultraviolet light emitting diodes (UV LEDs) configured with a polarization engineered Al0.75Ga0.25 N/In0.2Ga0.8 N tunnel junction structure. Tunnel-injected UV LED structure enables n-type contacts for both bottom and top contact layers. However, achieving Ohmic contact to wide bandga…

• FATİH AKYOL

We report on the cascading of blue light-emitting diodes (LEDs) up to three junctions using low-resistance InGaN tunnel junctions (TJs). At a forward current density of 10 A/cm 2 , triple- and dual-junction LEDs operated at 9.09 and 6.07 V with total differential resistances of 6.31 × 10 −2 and 4.16 × 10 −2 Ω cm 2 , r…

• FATİH AKYOL

In this work, we investigate the use of nanoscale polarization engineering to achieve efficient hole injection from metals to ultra-wide bandgap AlGaN, and we show that UV-reflective aluminum (Al) layers can be used for hole injection into p-AlGaN. The dependence of tunneling on the work function of the metal was inve…

• FATİH AKYOL

Background And Aims: Mirror therapy provides a novel, cost-effective approach to upper limb treatment following stroke. However, the effectiveness of mirror therapy in sub-acute stroke is unclear. Qualitative studies enable exploration and optimisation of intervention acceptability and implementation. This study explo…

• MEHMET RAŞİT ESKİCİOĞLU