عنوان

Fonksiyonel boya malzemeleri ve grafin alan etkitransistörleri kullanan fotodedektörlerin araştırılması

Number

TLpq2522839218

.Language of Text, Soundtrack etc

انگلیسی

Title Proper

Fonksiyonel boya malzemeleri ve grafin alan etkitransistörleri kullanan fotodedektörlerin araştırılması

General Material Designation

[Thesis]

First Statement of Responsibility

Yakar, Ozan

Subsequent Statement of Responsibility

Balcı, Sinan

Name of Publisher, Distributor, etc.

Izmir Institute of Technology (Turkey)

Date of Publication, Distribution, etc.

2020

Specific Material Designation and Extent of Item

47

Dissertation or thesis details and type of degree

Master's

Body granting the degree

Izmir Institute of Technology (Turkey)

Text preceding or following the note

2020

Text of Note

A J-aggregate dye is a type of water-soluble, functional dye, which has a sharp and narrow absorption peak after it self-assembles into a brick-wall structure at high concentrations. The absorption peak of the J-aggregates is sharp, narrow and shifted to longer wavelengths compared to their monomer form and it is in the visible or near infrared spectrum. Due to its very sharp and narrow absorption, it has been used in silver halide photography, non-linear optics, lasing and sensing applications. On the other hand, graphene is one atom layer thick, honeycomb lattice of carbon atoms. In the pure, freestanding form, the bands of its electronic structure touch at one point, making it a gapless semimetal. Due to this characteristic, it is possible to manipulate its optical and electronic properties by changing the Fermi energy of graphene. Therefore, graphene found applications in many fields such as light emitting diodes, photodetectors, Hall sensors, optical modulators and flexible optoelectronics. The functional dye materials have not been combined with graphene photodetectors even though they are highly sensitive to light, less toxic than their competitors and stable at room temperature. In this thesis, using a J-aggregate dye, which has a sharp absorption peak around 585 nm wavelength, a graphene phototransistor has been demonstrated. By changing the charge concentration on graphene, using the charge carriers that arise from the excitation of J-aggregate dye, reversible modulation of graphene Dirac point has been demonstrated. In addition, a novel thin film formation technique has been developed in this study. Porous polyethylene membrane has been used to create thin films of water-soluble materials, such as J-aggregates, on hydrophobic surfaces.

Engineering

Optical properties

Optics

Balcı, Sinan

Yakar, Ozan

Electronic name

p

[Thesis]

276903

a

Y