Characterization and Integration of Terahertz Technology within Microfluidic Platforms

Abstract

In this work, the prospects of integrating terahertz (THz) time-domain spectroscopy (TDS) within polymer-based microfluidic platforms are investigated. The work considers platforms based upon the polar polymers polyethylene terephthalate (PET), polycarbonate (PC), polymethyl-methacrylate (PMMA), polydimethylsiloxane (PDMS), and the nonpolar polymers fluorinated ethylene propylene (FEP), polystyrene (PS), high-density polyethylene (HDPE), and ultra-high-molecular-weight polyethylene (UHMWPE). The THz absorption coefficients for these polymers are measured. Two microfluidic platforms are then designed, fabricated, and tested, with one being based upon PET, as a representative high-loss polar polymer, and one being based upon UHMWPE, as a representative low-loss nonpolar polymer. It is shown that the UHMWPE microfluidic platform yields reliable measurements of THz absorption coefficients up to a frequency of 1.75 THz, in contrast to the PET microfluidic platform, which functions only up to 1.38 THz. The distinction seen here is attributed to the differing levels of THz absorption and the manifestation of differing f for the systems. Such findings can play an important role in the future integration of THz technology and polymer-based microfluidic systems.

Terahertz time domain spectroscopy of graphene and MXene polymer composites

“…The results obtained for pure PDMS sample are consistent with the literature values to the order of magnitude, 30,33 which does not match the resolution of the measurement. The absorption coefficient of PDMS is highly dependent on the fabrication process of the polymer, especially the curing temperature.…”

“…The shielding effectiveness ranges from highly shielding -40 dB graphene composite, through somewhat shielding (~6 dB) MXene composite, to low SE of pristine polymer. The MXene show surprisingly low SE when employed in a polymer composite, especially taking into account the SE of a MXene thin T A B L E 1 Comparison with previously reported absorption coefficients of studied nanomaterials or polymer composites with nanomaterial additives Material α (cm −1 ) @ 1 THz α (cm −1 ) @ 1.5 THz α (cm −1 ) @ 2 THz Pure PDMS 30 10.2 11.1 10.1…”

A Flexible and Ultra‐Wideband Terahertz Wave Absorber Based on Pyramid‐Shaped Carbon Nanotube Array via Femtosecond‐Laser Microprocessing and Two‐Step Transfer Technique

“…Over the past decades, terahertz (THz) waves (i.e., 0.3-3 THz) have attracted increasing attention for their unique properties and emerging applications in wireless communications, [1][2][3][4] absorption coefficients, especially at the lower end of the THz region. [19] Recently, numerous efforts have been made to design THz absorbers based on metamaterials or surface-relief structures, [20][21][22][23] to reduce the reflectance at the interface and thus to achieve a higher power absorptance. A THz metamaterial perfect absorber based upon a single-layer H-shaped metamaterials array on doped silicon substrate was demonstrated, exhibiting a resonance frequency blueshift by 0.42 THz via external optical pumping.…”

Terahertz Absorption Characteristics of the Sodium Carboxymethyl Cellulose Colloid Based on Microfluidic Technology

“…Leclerc et al [8] explored a direct and fast method to manufacture a microfluidic chip system using a polystyrene plate and computer micromachining technology. Alfihed et al [9] used the THz technology to detect various copolymers (e.g., PDMS, polycarbonate, and polyethylene terephthalate) and obtained stable THz absorption coefficient of polyethylene at a certain THz frequency, which showed the viability of the development of microfluidic technology.…”